DEVICE Reference Guide

Reference Guide

DEVICE

Release 3.1

1Contents

© 2003 - 2013 Lumerical Solutions, Inc

Table of ContentsPart I New Features 11

............................................................................................................ 111 New features for version 1.5



Part II Solver physics 15

............................................................................................................ 151 FDTD

................................................................................................................................................. 16FDTD and Maxwell's equations

................................................................................................................................................. 18Meshing in FDTD

............................................................................................................ 192 Eigenmode Solver

................................................................................................................................................. 20Meshing in the Eigenmode solver

............................................................................................................ 213 Propagator

................................................................................................................................................. 212.5D FDTD

................................................................................................................................................. 23Eigenmode expansion

................................................................................................................................................. 23Meshing in the propagator

............................................................................................................ 244 INTERCONNECT

................................................................................................................................................. 24Time Domain Simulator

................................................................................................................................................. 25Frequency Domain Simulator

............................................................................................................ 255 DEVICE

................................................................................................................................................. 25System of Equations

................................................................................................................................................. 28Meshing in DEVICE

Part III CAD layout editor 29

............................................................................................................ 291 Main title bar

............................................................................................................ 302 Toolbars

................................................................................................................................................. 30Main

................................................................................................................................................. 31Edit

................................................................................................................................................. 33Mouse mode

................................................................................................................................................. 34View

................................................................................................................................................. 35Simulation

................................................................................................................................................. 36Search bar

............................................................................................................ 363 View ports

............................................................................................................ 374 Object Tree

................................................................................................................................................. 37Enable/Disable Simulation Object

............................................................................................................ 385 Results View

............................................................................................................ 386 Optimization and Sweeps

............................................................................................................ 387 Script Prompt and Script Editor

............................................................................................................ 398 Script Workspace and Script Favorites

............................................................................................................ 399 Changing the CAD layout

Part IV Material database 42

Reference Guide2


............................................................................................................ 421 Material database

............................................................................................................ 432 Electrical models

................................................................................................................................................. 44Conductors

................................................................................................................................................. 44Insulators

................................................................................................................................................. 44Semiconductors

............................................................................................................ 543 Mesh order

Part V Simulation objects 56

............................................................................................................ 581 Structures

................................................................................................................................................. 58Primitives

................................................................................................................................................. 59Geometry tab

................................................................................................................................................. 59Material tab

................................................................................................................................................. 60Rotations tab

................................................................................................................................................. 60Graphical Rendering tab

................................................................................................................................................. 60Import Data tab

................................................................................................................................................. 65Properties tab

................................................................................................................................................. 65Script tab

............................................................................................................ 652 Simulation

................................................................................................................................................. 66General tab

................................................................................................................................................. 67Mesh tab

................................................................................................................................................. 67Geometry tab

................................................................................................................................................. 67Transient tab

................................................................................................................................................. 68Results

................................................................................................................................................. 68Advanced options tab

................................................................................................................................................. 69Solver type

................................................................................................................................................. 70Fermi statistics

............................................................................................................ 703 Monitors

................................................................................................................................................. 71General tab

................................................................................................................................................. 72Geometry tab

............................................................................................................ 724 Generation

............................................................................................................ 725 Doping

............................................................................................................ 746 Contacts

............................................................................................................ 767 Equation interpreter

Part VI Running simulations and analysis 77

............................................................................................................ 771 Resource Manager

................................................................................................................................................. 79Resources Advanced Options

............................................................................................................ 802 Running a simulation

............................................................................................................ 813 Analysis tools

................................................................................................................................................. 82Analysis tools and the simulation environment

................................................................................................................................................. 82Figure w indows for plots and images

................................................................................................................................................. 83Data export

................................................................................................................................................. 83Visualizer

................................................................................................................................................. 93Results Manager

............................................................................................................ 974 Optimization and parameter sweeps

3Contents


................................................................................................................................................. 99Optimization

................................................................................................................................................. 101Particle Swarm Optimization

................................................................................................................................................. 103Parameter Sweeps

................................................................................................................................................. 104Nested Sweeps

................................................................................................................................................. 105Yield Analysis

Part VII Scripting Language 108

............................................................................................................ 1091 System

................................................................................................................................................. 112newproject

................................................................................................................................................. 112newmode

................................................................................................................................................. 113save

................................................................................................................................................. 113load

................................................................................................................................................. 113del

................................................................................................................................................. 114rm

................................................................................................................................................. 114dir

................................................................................................................................................. 114ls

................................................................................................................................................. 115cd

................................................................................................................................................. 115pwd

................................................................................................................................................. 115cp

................................................................................................................................................. 116mv

................................................................................................................................................. 116exit

................................................................................................................................................. 116system

................................................................................................................................................. 117fileexists

................................................................................................................................................. 117currentfilename

................................................................................................................................................. 117filebasename

................................................................................................................................................. 118fileextension

................................................................................................................................................. 118filedirectory

................................................................................................................................................. 118getcommands

................................................................................................................................................. 118Run script

................................................................................................................................................. 119getpath

................................................................................................................................................. 119addpath

................................................................................................................................................. 119which

................................................................................................................................................. 120pause

................................................................................................................................................. 120break

................................................................................................................................................. 120Excape key

................................................................................................................................................. 121format

................................................................................................................................................. 121loaddata

................................................................................................................................................. 121savedata

................................................................................................................................................. 122savedcard

................................................................................................................................................. 122readdata

................................................................................................................................................. 123write

................................................................................................................................................. 123asapexport

................................................................................................................................................. 124asapload

................................................................................................................................................. 124asapimport

................................................................................................................................................. 124matlabsave

................................................................................................................................................. 125matlabsavelegacy

................................................................................................................................................. 125matlabload

................................................................................................................................................. 125matlab

................................................................................................................................................. 127matlabget

................................................................................................................................................. 127matlabput

Reference Guide4


................................................................................................................................................. 127copytoclipboard

................................................................................................................................................. 128pastefromclipboard

................................................................................................................................................. 128debug

................................................................................................................................................. 128vtksave

................................................................................................................................................. 129lookupread

................................................................................................................................................. 129lookupopen

................................................................................................................................................. 129lookupclose

................................................................................................................................................. 130lookupwrite

............................................................................................................ 1302 Manipulating variables

................................................................................................................................................. 132=

................................................................................................................................................. 132:

................................................................................................................................................. 132[]

................................................................................................................................................. 133%

................................................................................................................................................. 133linspace

................................................................................................................................................. 133matrix

................................................................................................................................................. 133randmatrix

................................................................................................................................................. 134randnmatrix

................................................................................................................................................. 134histogram

................................................................................................................................................. 134meshgridx

................................................................................................................................................. 135meshgridy

................................................................................................................................................. 135meshgrid3dx

................................................................................................................................................. 135meshgrid3dy

................................................................................................................................................. 136meshgrid3dz

................................................................................................................................................. 136meshgrid4d

................................................................................................................................................. 136clear

................................................................................................................................................. 136workspace

................................................................................................................................................. 137Accessing and assigning matrix elements

................................................................................................................................................. 138Matrix operators

................................................................................................................................................. 138Pre-defined constants

................................................................................................................................................. 139matrixdataset

................................................................................................................................................. 139rectilineardataset

................................................................................................................................................. 140addparameter

................................................................................................................................................. 140addattribute

................................................................................................................................................. 140getparameter

................................................................................................................................................. 141getattribute

................................................................................................................................................. 141eye

................................................................................................................................................. 141Datasets

................................................................................................................................................. 146struct

................................................................................................................................................. 147cell

................................................................................................................................................. 147unstructureddataset

............................................................................................................ 1483 Operators

................................................................................................................................................. 149.

................................................................................................................................................. 150*

................................................................................................................................................. 150/

................................................................................................................................................. 150+

................................................................................................................................................. 150-

................................................................................................................................................. 151^

................................................................................................................................................. 151==

................................................................................................................................................. 151almostequal

................................................................................................................................................. 152!=

5Contents


................................................................................................................................................. 152<=

................................................................................................................................................. 152>=

................................................................................................................................................. 153<

................................................................................................................................................. 153>

................................................................................................................................................. 153&

................................................................................................................................................. 153and

................................................................................................................................................. 154|

................................................................................................................................................. 154or

................................................................................................................................................. 154!

................................................................................................................................................. 155~

................................................................................................................................................. 155"

................................................................................................................................................. 156'

................................................................................................................................................. 157endl

................................................................................................................................................. 157?

................................................................................................................................................. 157comments

............................................................................................................ 1574 Functions

................................................................................................................................................. 162sin

................................................................................................................................................. 162cos

................................................................................................................................................. 162tan

................................................................................................................................................. 162asin

................................................................................................................................................. 163acos

................................................................................................................................................. 163atan

................................................................................................................................................. 163atan2

................................................................................................................................................. 164real

................................................................................................................................................. 164imag

................................................................................................................................................. 164conj

................................................................................................................................................. 164abs

................................................................................................................................................. 165angle

................................................................................................................................................. 165unwrap

................................................................................................................................................. 165log

................................................................................................................................................. 165log10

................................................................................................................................................. 166sqrt

................................................................................................................................................. 166exp

................................................................................................................................................. 166size

................................................................................................................................................. 166length

................................................................................................................................................. 167pinch

................................................................................................................................................. 167sum

................................................................................................................................................. 168max

................................................................................................................................................. 168min

................................................................................................................................................. 168dot

................................................................................................................................................. 168cross

................................................................................................................................................. 169eig

................................................................................................................................................. 169mult

................................................................................................................................................. 170flip

................................................................................................................................................. 170permute

................................................................................................................................................. 170reshape

................................................................................................................................................. 171inv

................................................................................................................................................. 171interp

................................................................................................................................................. 172interptri

................................................................................................................................................. 172spline

Reference Guide6


................................................................................................................................................. 173integrate

................................................................................................................................................. 173integrate2

................................................................................................................................................. 174find

................................................................................................................................................. 174findpeaks

................................................................................................................................................. 175transpose

................................................................................................................................................. 175ctranspose

................................................................................................................................................. 175num2str

................................................................................................................................................. 176str2num

................................................................................................................................................. 176eval

................................................................................................................................................. 176feval

................................................................................................................................................. 176substring

................................................................................................................................................. 177findstring

................................................................................................................................................. 177replace

................................................................................................................................................. 178replacestring

................................................................................................................................................. 178splitstring

................................................................................................................................................. 178fft

................................................................................................................................................. 180fftw

................................................................................................................................................. 181fftk

................................................................................................................................................. 182invfft

................................................................................................................................................. 183czt

................................................................................................................................................. 183polyarea

................................................................................................................................................. 184centroid

................................................................................................................................................. 184polyintersect

................................................................................................................................................. 185inpoly

................................................................................................................................................. 185polygrow

................................................................................................................................................. 186polyand

................................................................................................................................................. 186polyor

................................................................................................................................................. 186polydiff

................................................................................................................................................. 187polyxor

................................................................................................................................................. 187lineintersect

................................................................................................................................................. 188linecross

................................................................................................................................................. 188ceil

................................................................................................................................................. 188floor

................................................................................................................................................. 189mod

................................................................................................................................................. 189sign

................................................................................................................................................. 189round

................................................................................................................................................. 190rand

................................................................................................................................................. 190lognrnd

................................................................................................................................................. 190randn

................................................................................................................................................. 191randreset

................................................................................................................................................. 191finite

................................................................................................................................................. 191solar

................................................................................................................................................. 192stackrt

................................................................................................................................................. 192mean

................................................................................................................................................. 192all

................................................................................................................................................. 193any

................................................................................................................................................. 193var

................................................................................................................................................. 194std

................................................................................................................................................. 194mapfind

................................................................................................................................................. 195quadtri

................................................................................................................................................. 195expand

7Contents


................................................................................................................................................. 196norm

............................................................................................................ 1965 Loop and conditional statements

................................................................................................................................................. 196for

................................................................................................................................................. 197if

............................................................................................................ 1976 Plotting commands

................................................................................................................................................. 198plot

................................................................................................................................................. 199plotxy

................................................................................................................................................. 200polar

................................................................................................................................................. 200polar2

................................................................................................................................................. 201polarimage

................................................................................................................................................. 202histc

................................................................................................................................................. 202legend

................................................................................................................................................. 202image

................................................................................................................................................. 203visualize

................................................................................................................................................. 204selectfigure

................................................................................................................................................. 204setplot

................................................................................................................................................. 204exportfigure

................................................................................................................................................. 205closeall

................................................................................................................................................. 205vectorplot

............................................................................................................ 2057 Adding Objects

................................................................................................................................................. 208switchtolayout

................................................................................................................................................. 209layoutmode

................................................................................................................................................. 209addgroup

................................................................................................................................................. 209addstructuregroup

................................................................................................................................................. 210addanalysisgroup

................................................................................................................................................. 210addobject

................................................................................................................................................. 210addcontact

................................................................................................................................................. 211addcircle

................................................................................................................................................. 211addcustom

................................................................................................................................................. 211addimport

................................................................................................................................................. 212addpyramid

................................................................................................................................................. 212addpoly

................................................................................................................................................. 212addrect

................................................................................................................................................. 213addtriangle

................................................................................................................................................. 213addring

................................................................................................................................................. 213addsphere

................................................................................................................................................. 214addsurface

................................................................................................................................................. 214addfdtd

................................................................................................................................................. 214addeigenmode

................................................................................................................................................. 214addpropagator

................................................................................................................................................. 215addmesh

................................................................................................................................................. 215addmode

................................................................................................................................................. 215addmodesource

................................................................................................................................................. 215adddipole

................................................................................................................................................. 216addgaussian

................................................................................................................................................. 216addplane

................................................................................................................................................. 216addtfsf

................................................................................................................................................. 217addimportedsource

................................................................................................................................................. 217addindex

................................................................................................................................................. 217addtime

Reference Guide8


................................................................................................................................................. 218addmovie

................................................................................................................................................. 218addprofile

................................................................................................................................................. 218createbeam

................................................................................................................................................. 219adddevice

................................................................................................................................................. 219adddope

................................................................................................................................................. 219adddiffusion

................................................................................................................................................. 219addimportdope

................................................................................................................................................. 220addbulkgen

................................................................................................................................................. 220addimportgen

................................................................................................................................................. 220addgridattribute

................................................................................................................................................. 221addelement

................................................................................................................................................. 222addmodeexpansion

................................................................................................................................................. 222addeffectiveindex

................................................................................................................................................. 222addchargemonitor

................................................................................................................................................. 223addfieldmonitor

............................................................................................................ 2238 Manipulating objects

................................................................................................................................................. 226groupscope

................................................................................................................................................. 226deleteall

................................................................................................................................................. 227delete

................................................................................................................................................. 227selectall

................................................................................................................................................. 227unselectall

................................................................................................................................................. 227select

................................................................................................................................................. 228selectpartial

................................................................................................................................................. 228shiftselect

................................................................................................................................................. 229shiftselectpartial

................................................................................................................................................. 229flipelement

................................................................................................................................................. 229rotateelement

................................................................................................................................................. 229move

................................................................................................................................................. 230copy

................................................................................................................................................. 230addtogroup

................................................................................................................................................. 231adduserprop

................................................................................................................................................. 231set

................................................................................................................................................. 232setnamed

................................................................................................................................................. 232setglobalmonitor

................................................................................................................................................. 233setglobalsource

................................................................................................................................................. 233setmodes

................................................................................................................................................. 233setposition

................................................................................................................................................. 234setrectangle

................................................................................................................................................. 234getposition

................................................................................................................................................. 234getrectangle

................................................................................................................................................. 235get

................................................................................................................................................. 235runsetup

................................................................................................................................................. 236getnumber

................................................................................................................................................. 236getnamed

................................................................................................................................................. 237getnamednumber

................................................................................................................................................. 237getglobalmonitor

................................................................................................................................................. 237getglobalsource

................................................................................................................................................. 238getsolver

................................................................................................................................................. 238haveproperty

................................................................................................................................................. 238importsurface

9Contents


................................................................................................................................................. 240importsurface2

................................................................................................................................................. 241importnk

................................................................................................................................................. 243importnk2

................................................................................................................................................. 245importnkobfuscated

................................................................................................................................................. 246importbinary

................................................................................................................................................. 248importbinary2

................................................................................................................................................. 250importbinaryobfuscated

................................................................................................................................................. 251updatesourcemode

................................................................................................................................................. 252setsourcesignal

................................................................................................................................................. 253updatemodes

................................................................................................................................................. 254clearsourcedata

................................................................................................................................................. 254clearmodedata

................................................................................................................................................. 255seteigensolver

................................................................................................................................................. 256geteigensolver

................................................................................................................................................. 256redraw

................................................................................................................................................. 257redrawoff

................................................................................................................................................. 257redrawon

................................................................................................................................................. 257redrawmode

................................................................................................................................................. 258setview

................................................................................................................................................. 259getview

................................................................................................................................................. 259orbit

................................................................................................................................................. 260framerate

................................................................................................................................................. 260undo

................................................................................................................................................. 260redo

................................................................................................................................................. 261addport

................................................................................................................................................. 261removeport

................................................................................................................................................. 262connect

................................................................................................................................................. 262disconnect

................................................................................................................................................. 262setexpansion

................................................................................................................................................. 263removeexpansion

................................................................................................................................................. 263setactivesolver

................................................................................................................................................. 263getname

................................................................................................................................................. 263setname

................................................................................................................................................. 264importdataset

................................................................................................................................................. 264cleardataset

............................................................................................................ 2659 Running simulations

................................................................................................................................................. 265runparallel

................................................................................................................................................. 266addjob

................................................................................................................................................. 266runjobs

................................................................................................................................................. 266clearjobs

................................................................................................................................................. 267runsweep

............................................................................................................ 26710 Measurement and optimization data

................................................................................................................................................. 268getsweepdata

................................................................................................................................................. 269getsweepresult

................................................................................................................................................. 269getdata

................................................................................................................................................. 270getresult

................................................................................................................................................. 270runanalysis

................................................................................................................................................. 271havedata

................................................................................................................................................. 271haveresult

................................................................................................................................................. 272havesweepdata

Reference Guide10


................................................................................................................................................. 272havesweepresult

................................................................................................................................................. 273copydcard

................................................................................................................................................. 273clearanalysis

................................................................................................................................................. 274cleardcard

................................................................................................................................................. 274getelectric

................................................................................................................................................. 274getmagnetic

................................................................................................................................................. 275Read and write data to files

................................................................................................................................................. 275loadsweep

................................................................................................................................................. 275savesweep

............................................................................................................ 27611 Material database

................................................................................................................................................. 276addmaterial

................................................................................................................................................. 277copymaterial

................................................................................................................................................. 277setmaterial

................................................................................................................................................. 277getmaterial

................................................................................................................................................. 278getindex

................................................................................................................................................. 278getfdtdindex

................................................................................................................................................. 279getmodeindex

................................................................................................................................................. 280getnumericalpermittivity

............................................................................................................ 28112 GDSII

................................................................................................................................................. 282gdsopen

................................................................................................................................................. 282gdsclose

................................................................................................................................................. 283gdsbegincell

................................................................................................................................................. 283gdsendcell

................................................................................................................................................. 284gdsaddpoly

................................................................................................................................................. 284gdsaddcircle

................................................................................................................................................. 285gdsaddrect

................................................................................................................................................. 286gdsaddref

................................................................................................................................................. 286gdsimport

............................................................................................................ 28813 User defined GUIs

................................................................................................................................................. 288message

................................................................................................................................................. 289newwizard

................................................................................................................................................. 289newwizardpage

................................................................................................................................................. 289wizardwidget

................................................................................................................................................. 290wizarddata

................................................................................................................................................. 291runwizard

................................................................................................................................................. 291wizardgetdata

................................................................................................................................................. 291killw izard

................................................................................................................................................. 292wizardoption

................................................................................................................................................. 292fileopendialog

................................................................................................................................................. 292filesavedialog

............................................................................................................ 29314 Creating your own script commands

Index 295

New Features 11


1 New Features

DEVICE is constantly being upgraded. See the following sections for a list of the latestnew features.

New features for version 1.5New features for version 2.0New features for version 3.1

1.1 New features for version 1.5New solver option

In the initial versions of the software, the Gummel’s method was used in the solver, inwhich the voltage and charge were solved sequentially (one was used as a input to theother) until the two were consistent. In DEVICE 1.5, the Newton solver has beenintroduced, which solves for the charge and voltage simultaneously. The Newton solver ismore sensitive to the initial conditions (it may not converge), but will converge much fasterfor a wider variety of problems if it’s given a good initial guess.

Advanced contact models

Several modificationshave been made to thecontact models forDEVICE:

Lumped elementloads (R and C) cannow be added ondevice terminals. Customspecification of DCsweep bias voltagesis available. Non-ohmic contactswill use a Schottkybarrier modelaccounting forbarrier lowering dueto the appliedelectric field.

11

12

13

Reference Guide12


Adaptive transient simulation

Transient simulations now employ adaptive time-stepping to optimally vary the simulationinterval while maintaining accuracy. Coupled with the full Newton solver, a wider variety oftransient simulations can now be performed efficiently with DEVICE. To view the newsettings associated with the transient simulation, consult the "Transient" tab in the Deviceregion properties. Here, the user may specify time step constraints, down-sampling, andshuttering for optical generation objects.

Results selection

In the Device region properties, users now how the option to retain a reduced set of spatialdata. Under the "Results" tab, a list of all available results can be viewed, and may betoggled on or off to reduce memory requirements. By default all results are included.

1.2 New features for version 2.0Results manager and VisualizerThe Results Manager is a tool for analyzing simulation data. This includes a ResultsView window which displays all the results for the simulation object that is currentlyselected in the Object Tree. The Results Manager also includes a Script Workspace and aScript Favorites window, providing additional GUI-based functionalities.

Also featured in DEVICE 2.0 is the more improved Visualizer , which significantlysimplifies the process of visualizing simulation data. When used in conjunction, ResultsManager and the Visualizer provide a very useful and intuitive way of analyzing andvisualizing variables and results through the GUI, greatly reducing the need for scripting.

DatasetsLumerical datasets are structured data objects that collect a set of related matrices into asingle convenient object. See Dataset introduction for more information.

Yield analysis toolA new yield analysis tool is available in the Optimization and Sweeps window. The yieldanalysis tool gives users the ability to run extensive Monte Carlo analysis, sweeping

93

83

141

New Features 13


across multiple parameters to assess statistical variations of circuit elements on overallcircuit performance.

Please see the Yield analysis page in the Reference Guide for more details, and theRunning a yield analysis task example in the User Guide.

Other new script commandsThe following script functions were added in DEVICE 2.0. For more information, see thefunction descriptions in the scripting section of the Reference Guide.. operator , addattribute , addparameter , eig , debug ,getattribute , getparameter , getresult , getsweepresult ,integrate2 , matrixdataset , addmodeexpansion , mult ,permute rectilineardataset , reshape

1.3 New features for version 3.1 3D solver

DEVICE is now capable of simulating fully three dimensional geometries. The solver typecan be chosen by the user to be 2D or 3D. This means that arbitrary structures particularlywhere slicing or averaging of imported 3D data is not valid can now be solved for in 3dimensions.

Visualization

The visualizer has been updated for 3D simulations to allow the user to better view theresults, enabling image plots, arbitrary slices of the 3D geometry or line plots of varioustypes of data.

Field and charge monitors

A new object type, monitor, has been added to DEVICE. 2D/3D monitors can be placedanywhere within the simulation region to record the total charge within the monitor and/orelectric field through the monitor boundaries.

Continue from previous solution

It is now possible to specify a project file that has already been run as a reference projectfor solving another simulation. The initialization step in the solver can be skipped with thisfeature, using the converged solution of the specified file. This will save a lot of time inmemory intensive simulations.

105

149 140 140 169 128

141 140 270 269

173 139 222 169

170 139 170

Reference Guide14


Electron-hole density grid attributeFDTD Solutions 8.7 and MODE Solutions 6.6 (and beyond) can import electron-holedensity data recorded on a finite-element mesh directly from a DEVICE simulation. Thisapproach, which offers significant improvement over the previous (n, k) import option,reduces simulation memory requirements and interpolation errors.

XML lookup table supportAs of version 3.0, users can simulate a wide range of device designs with Lumerical'sTCAD tools, the results of which get incorporated into an XML lookup table. This XMLlookup table can then be associated with a specific element as the basis for a validatedcompact model within an INTERCONNECT project. Please see Parameter Extraction andPDKs for detailed examples.

Export viewports to imageAs of version 3.1, users can export CAD viewports into JPEG figures by selecting "View ->Export view" from the main title bar.

new script commandsThe following script functions were added in DEVICE 3.0. For more information, see thefunction descriptions in the scripting section of the Reference Guide. all, any, quadtri, unstructuredataset, loadsweep, savesweep,var, std

Solver physics 15


2 Solver physics

This chapter describes the basic physics and algorithms used in Lumerical's various'Physics' based solvers:

FDTD SolutionsThe Finite-Difference Time-Domain method, which is the method behind both FDTDSolutions and MODE Solutions' Propagator.

MODE Solutions Eigenmode SolverThe method behind MODE Solutions' Eigenmode Solver and FDTD Solutions' IntegratedMODE Solver.

MODE Solutions PropagatorThe method behind MODE Solutions' omnidirectional propagator for planar integratedsystems.

INTERCONNECTThe method behind Lumerical's INTERCONNECT circuit simulator.

DEVICEThe method behind Lumerical's DEVICE electronic device simulator.

2.1 FDTDThe finite-difference time-domain (FDTD) method1,2,3 is a state-of-the-art method for solvingMaxwell's equations in complex geometries. Being a direct time and space solution, itoffers the user a unique insight into all types of problems in electromagnetics andphotonics. In addition, FDTD can also obtain the frequency solution by exploiting Fouriertransforms, thus a full range of useful quantities can be calculated, such as the complexPoynting vector and the transmission / reflection of light.

This section will introduce the basic mathematical and physics formalism behind the FDTDalgorithm used in FDTD Solutions and MODE Solutions' propagator, starting from the linearMaxwell's equations. The simulator can be used for advanced research and development oras an ideal teaching and learning environment in photonics, optics, and electromagnetics.

See the FDTD Numerical methods video for additional information: http://www.lumerical.com/support/courses/fdtd_numerical_methods/video.html

15

19

21

24

25

http://www.lumerical.com/support/courses/fdtd_numerical_methods/video.html

http://www.lumerical.com/support/courses/fdtd_numerical_methods/video.html

Reference Guide16


1 Dennis M. Sullivan, Electromagnetic simulation using the FDTD method. New York: IEEEPress Series, (2000).2 Allen Taflove, Computational Electromagnetics: The Finite-Difference Time-DomainMethod. Boston: Artech House, (2005).3 Stephen D. Gedney, Introduction to the Finite-Difference Time-Domain (FDTD) Method forElectromagnetics. Morgan & Claypool publishers, (2011).

2.1.1 FDTD and Maxwell's equations

FDTD solves Maxwell's curl equations in non-magnetic materials:

Ht

D

)()()( 0 ED r

Et

H

0

1

where H, E, and D are the magnetic, electric, and displacement fields, respectively, while

)(r is the complex relative dielectric constant (

2)( nr, where n is the refractive

index).

In three dimensions, Maxwell equations have six electromagnetic field components: Ex, E

y,

Solver physics 17


Ez and H

x, H

y, and H

z. If we assume that the structure is infinite in the z dimension and

that the fields are independent of z, specifically that

),,(),,,( yxzyx rr

0z

H

z

E

then Maxwell's equations split into two independent sets of equations composed of threevector quantities each which can be solved in the x-y plane only. These are termed the TE(transverse electric), and TM (transverse magnetic) equations. We can solve both sets ofequations with the following components:TE: E

x, E

y, H

z

TM: Hx, H

y, E

z

For example, in the TM case, Maxwell's equations reduce to:

y

H

x

H

t

D xyz

)()()( 0 zrz ED

y

E

t

H zx

0

1

x

E

t

Hzy

0

1

FDTD Solutions can solve the two and three dimensional Maxwell's equations in dispersivemedia and some simple non-linear media, where the user can specify arbitrary geometricstructures and various input excitation sources. The two dimensional FDTD simulatorsolves the TE and/or TM Maxwell equations.

FDTD is a time domain technique, meaning that the electromagnetic fields are solved as afunction of time. In general, FDTD Solutions is used to calculate the electromagnetic fieldsas a function of frequency or wavelength by performing Fourier transforms during thesimulation. This allows it to obtain complex-valued fields and other derived quantities suchas the complex Poynting vector, normalized transmission, and far field projections as afunction of frequency or wavelength. The field information can be returned in two differentnormalization states, please see the section on frequency domain normalization for moredetails.

Reference Guide18


Dispersive materials with tabulated refractive index (n,k) data as a function of wavelengthcan be solved using the multi-coefficient models with auto-fitting. Alternatively, specifictheoretical models such as Plasma (Drude), Debye or Lorentz can be used. See thechapter on the Material Database for details.

Boundary conditions are very important in electromagnetics and simulation techniques. FDTD Solutions/propagator supports a range of boundary conditions, such as PML,periodic, and Bloch. See the boundary conditions section here for the complete list.

Sources are another important component of a simulation. FDTD Solutions/propagatorsupports a number of different types of sources such as point dipoles, beams, plane waves,a total-field scattered-field (TFSF) source, a guided-mode source for integrated opticalcomponents, and an imported source to interface with external photonic design softwares. Detailed information about each of these sources is contained in the Radiation sourcessection.

Unless otherwise specified, all quantities in FDTD Solutions/propagator are calculated in SIunits. Please see Units and Normalization for more information.

The online User Guide at http://docs.lumerical.com/en/fdtd/knowledge_base.html has manymore details about the physics of FDTD and how to obtain advanced results. Please see,for example, the sections on coherence, and far field calculations in the online User Guide.

2.1.2 Meshing in FDTD

FDTD Solutions uses a rectangular, Cartesian style mesh, like the one shown in thefollowing screenshot. It's important to understand that of the fundamental simulationquantities (material properties and geometrical information, electric and magnetic fields) arecalculated at each mesh point. Obviously, using a smaller mesh allows for a moreaccurate representation of the device, but at a substantial cost. As the mesh becomessmaller, the simulation time and memory requirements will increase. FDTD Solutionsprovides a number of features, including the conformal mesh algorithm, that allow you toobtain accurate results, even when using a relatively coarse mesh.

By default, the simulation mesh is automatically generated.To maintain accuracy, the meshing algorithm will create asmaller mesh in high index (to maintain a constant numberof mesh points per wavelength) and highly absorbing(resolve penetration depths) materials. In some cases, it isalso necessary to manually add additional meshingconstraints. Usually, this involves forcing the mesh to besmaller near complex structures (often metal) where thefields are changing very rapidly.

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Solver physics 19


2.2 Eigenmode SolverThe Eigenmode Solver (Eigensolver) solves for optical modes in a cross-section of anarbitrary waveguide geometry. The waveguide mode as a transverse field distribution thatpropagates along the waveguide without changing shape.

In the z-normal eigenmode solver simulation example shown in the figure above, we havethe vector fields:

)(),( ztieyxE and

)(),( ztieyxH

where ω is the angular frequency and β is the propagation constant. The modal effective

index is then defined as

cneff

.

MODE Solutions find these modes by solving Maxwell's equations on a cross-sectionalmesh of the waveguide. The finite difference algorithm is the current method used formeshing the waveguide geometry, and has the ability to accommodate arbitrary waveguidestructure. Once the structure is meshed, Maxwell's equations are then formulated into amatrix eigenvalue problem and solved using sparse matrix techniques to obtain the effective

index and mode profiles of the waveguide modes. This method is based on Zhu and Brown1

, with proprietary modifications and extensions.

Reference Guide20


Z. Zhu and T. G. Brown, “Full-vectorial finite-difference analysis of microstructured opticalfibers,” Opt. Express 10, 853–864 (2002), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-10-17-853

2.2.1 Meshing in the Eigenmode solver

The MODE Solutions Eigenmode Solver uses a rectangular, Cartesian style mesh, like theone shown in the following screenshot. It's important to understand that of the fundamentalsimulation quantities (material properties and geometrical information, electric andmagnetic fields) are calculated at each mesh point. Obviously, using a smaller meshallows for a more accurate representation of the device, but at a substantial cost. As themesh becomes smaller, the simulation time and memory requirements will increase. MODE Solutions provides a number of features, including the conformal mesh algorithm,that allow you to obtain accurate results, even when using a relatively coarse mesh.

By default, the simulation will use a uniform mesh. You simply set the number of mesh points alongeach axis. In some cases, it is necessary to addadditional meshing constraints. Usually, this involvesforcing the mesh to be smaller near complexstructures where the fields are changing very rapidly.

Note: In FDTD-based simulations, it's important touse a smaller mesh in high index materials, and tomaintain a minimum number of mesh points perwavelength. This constraint does not exist for theEigenmode solver.

Solver physics 21


2.3 PropagatorMODE Solutions currently supports 2 methods of propagating fields.

1) The 2.5D FDTD propagator. This propagator accurately describes the propagation oflight in planar integrated optical systems, from ridge waveguide-based systems to morecomplex geometries such as photonic crystals. The propagator allows for planar (omni-directional) propagation without any assumptions about an optical axis, which allows forstructures like ring resonators and photonic crystal cavities to be efficiently modeled –devices that have been traditionally treated with 3D FDTD. The propagator can modeldevices on the scale of hundreds of microns quickly.

2) The eigenmode expansion propagator. This script based, unidirectional eigenmodeexpansion propagator allows you to decompose one input or waveguide mode onto themodes of another waveguide section and propagate the modes an arbitrary distance. It isuseful for waveguide couplers, long tapers and other devices where the propagation can beassumed to be essentially unidirectional.

2.3.1 2.5D FDTD

The FDTD propagator is based on collapsing a 3D geometry into a 2D set of effectiveindices that can be solved with 2D FDTD . This works best with waveguides made fromplanar structures. For additional information on the 2.5D Propagator, see the Lumerical’s2.5D FDTD Propagation Method whitepaper on our website.

The main assumption of this method is that there is little coupling between differentsupported slab modes. For many devices, such as SOI based slab waveguide structures,that only support 2 vertical modes with different polarizations, this is an excellentassumption.

The calculation steps involve:1. Identification of the vertical slab modes of the core waveguide structure, over a desired

range of wavelengths. 2. Meshing of the structure and collapse of the 3rd dimension by calculation of the

corresponding effective 2D indices (taking into account the vertical slab mode profile).There are currently two approaches to doing this in the Propagator:

VariationalA variational procedure based on Hammer and Ivanova1. Here, the effective permittivities ofthe TE and TM-like modes have the form:

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http://www.lumerical.com/solutions/innovation/2.5d_fdtd_propagation_method.html

http://www.lumerical.com/solutions/innovation/2.5d_fdtd_propagation_method.html

Reference Guide22


z

z

r

rTEeff

dzzM

dzzMzzyx

kyx

2

2

2

),(

),(),(),,(

),,(

z

z r

z

z rrTMeff

dzMzyx

k

dzz

M

zyx

dzMzyx

dzM

kyx

22

2

2

22

),,(

1

),,(

11

||),,(

1

||1

),,(

where εr, M and βr are the 1-D reference permittivity profile, the associated guided slabmode and the propagation constant.

Reciprocity BasedThis is a procedure based on the reciprocity theorem, as described in Snyder and Love2:

z

z

r

reff

dznP

dzzEzzyx

kyxn

2

2

1

0

0

),(),(),,(

),,(

Note that in both cases, the generated effective materials are also dispersive, where thedispersion comes both from the original material properties (material dispersion) and theslab waveguide geometry (waveguide dispersion). These new materials are then fitted usingLumerical Solutions' multi-coefficient model into a time-domain form that can be used in the2D FDTD simulation in step 3. Note that the effective index treatment may lead togenerated materials that have properties that are unphysical (for example, having anartificial negative imaginary index). In this case, one has the option of restricting the rangeof generated indices to the min/max values defined by the physical material properties ofthe original materials. All of these settings can be found under the Effective index tab of thePropagator simulation region.

3. Simulation of the structure in 2D by FDTD .4. If desired, re-expansion of the fields into 3D.

The Ring resonator getting started example contains step-by-step instructions anddiscussions on how to carry out a propagator simulation using the variational FDTDmethod.

1 Manfred Hammer and Olena V. Ivanova, MESA Institute for Nanotechnology, University ofTwente, Enschede, The Netherlands

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Solver physics 23


"Effective index approximation of photonic crystal slabs: a 2-to-1-D assessment", Opticaland Quantum Electronics ,Volume 41, Number 4, 267-283, DOI: 10.1007/s11082-009-9349-32 Allan W. Snyder and John D. Love, Optical Waveguide Theory. Chapman & Hall, London,England, 1983.

2.3.2 Eigenmode expansion

This unidirectional eigenmode expansion method is implemented in the propagatecommand.

The propagate command calculates the resulting mode profile of an arbitrary mode after ithas propagated through a waveguide for some distance. This is done by decomposing themode into modes supported by the waveguide (ie. the currently calculated modes) using overlap integrals. Each supported mode is then propagated through the waveguide. Theresulting modes are then added coherently to give the final mode profile.

This technical is useful for waveguide couplers, long tapers and other devices where thepropagation can be assumed to be essentially uni-directional. Please see MODE Solutions'applications library for some use case examples:Evanescent waveguide couplersTapered waveguidesPolarization rotator

2.3.3 Meshing in the propagator

The MODE Solutions Propagator uses a rectangular, Cartesian style mesh, like the oneshown in the following screenshot. It's important to understand that of the fundamentalsimulation quantities (material properties and geometrical information, electric andmagnetic fields) are calculated at each mesh point. Obviously, using a smaller meshallows for a more accurate representation of the device, but at a substantial cost. As themesh becomes smaller, the simulation time and memory requirements will increase. MODE Solutions provides a number of features, including the conformal mesh algorithm,that allow you to obtain accurate results, even when using a relatively coarse mesh.

By default, the simulation mesh is automaticallygenerated. To maintain accuracy, the meshingalgorithm will create a smaller mesh in high index (tomaintain a constant number of mesh points perwavelength) and highly absorbing (resolve penetrationdepths) materials. In some cases, it is alsonecessary to manually add additional meshingconstraints. Usually, this involves forcing the mesh tobe smaller near complex structures (often metal)

Reference Guide24


where the fields are changing very rapidly.

Note: meshing timeThe general meshing algorithm can take a reasonable amount of time compared to thesimulation because the mesh must be effectively completed in 3D. It is possible for theuser to specify if the structure is composed of purely extruded structures - that isstructures that are extruded along z with perfectly vertical sidewalls. In this case, themeshing can be accomplished much faster.

2.4 INTERCONNECTINTERCONNECT is a circuit simulator that can support mixed signal representation ofoptical single and multi-mode signals as well as electrical signals. The signals canpropagate fully bidirectionally through the circuit topology for both Time Domain andFrequency Domain simulations.

Users can choose elements from an extensive list of pre-defined PIC elements, as well ascreate custom elements from pre-defined primitives or via Lumerical’s powerful scriptlanguage. In addition, elements can also be characterized accurately using results directlyfrom Lumerical's electromagnetic simulators (FDTD Solutions and MODE Solutions).

2.4.1 Time Domain Simulator

Time domain simulation is performed using a data flow system simulator, allowing for moreflexibility than using traditional discrete time or time-driven simulators. The simulatorscheduler calculates each element in order to generate time domain waveform samples andpropagate them bidirectionally. Very close coupling between components can be simulatedallowing, for example, the analysis of optical resonators.

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Solver physics 25


2.4.2 Frequency Domain Simulator

Frequency domain simulation is performed using scattering data analysis to calculate theoverall circuit response.

The circuit is composed a series of elements connected by an arbitrary number of input/output (or bidirectional) ports. Users can define all the modes supported by the device andtheir frequency dependent properties.

Once all the ports are defined, INTERCONNECT carries out the scattering data analysis forthe entire circuit by solving a sparse matrix that represents the circuit as connectedscattering matrices, each one of them representing the frequency response of an individualelement.

2.5 DEVICEDEVICE is an physics-based electrical simulation tool for semiconductors, which self-consistently solves the system of equations describing the electrostatic potential anddensity of free charge (electrons and holes). DEVICE solves the drift-diffusion equation todescribe the spatial distribution of electrons and holes, and solves the Poisson equation toestablish the electrostatic potential. Solving the drift-diffusion (DD) equations is anestablished and robust method that will produce accurate results for a wide range ofsemiconductor devices under common operating conditions.

This section will introduce the basic mathematical and physics formalism behind the self-consistent algorithm used in DEVICE, starting from the non-linear Poisson and drift-diffusion equations. The simulator can be used for advanced research and development oras an ideal teaching and learning environment in semiconductor electronics andoptoelectronics.

2.5.1 System of Equations

DEVICE solves the drift-diffusion equations for electrons and holes (carriers)

nqDnq nnn EJ

pqDpq ppp EJ

where Jn,p is the current density (A/cm2), q is the positive electron charge, µ n,p is themobility, E is the electric field, Dn,p is the diffusivity, and n and p are the densities of the

Reference Guide26


electrons and holes, respectively (the subscripts n and p indicate quantities that arespecific to the carrier type). Each carrier (electron or hole) moves under the influence of twocompeting processes: drift due to the applied electric field, and random thermal diffusiondue to the gradient in the density. These processes are represented in the drift-diffusionequations as the sum of two terms.

The mobility µ n,p describes the ease with which carriers can move through thesemiconductor material, and is related to the diffusivity Dn,p through the Einstein relation

q

TkD B

pnpn ,,

where kB is the Boltzmann constant. The mobility is a key property of the material, andmay be modeled as a function of temperature, impurity (doping) concentration, carrierconcentration, and electric field. For further details, please see the section on materialmodels.

To solve the drift-diffusion equations, the electric field must be known. To determine theelectric field, Poisson's equation is solved:

qV

where ε is the dielectric permittivity, V the electrostatic potential )( VE

and ρ thenet charge density,

Cnp

which includes the contribution C from the ionized impurity density.

Finally, the auxiliary continuity equations are required to account for charge conservation

nn Rqt

nJ

1

pp Rqt

pJ

1

where Rn,p is the net recombination rate (the difference between the recombination rateand generation rate). The physical processes associated with the material are assumed toact equivalently when applied to electrons or holes, and as a result, R = Rn = Rp. Therecombination and generation processes are important factors in the material-specificcalculation of carrier behavior. Multiple recombination and generation processes aremodeled, which may depend on temperature, impurity (doping) concentration, carrierconcentration, electric field, and current density. For further details, please see the sectionon material models.

Solver physics 27


DEVICE discretizes and solves the drift-diffusion and Poisson’s equations on anunstructured finite-element mesh in one and two dimensions. The simulation region ispartitioned into multiple domains along boundaries between materials with unique physicaldescriptions. The materials used in the simulation may be categorized as insulators,semiconductors, or conductors; each type of material has an associated user-specifiedmodel or collection of models that describe its behavior. In particular, specialized multi-coefficient models are provided for semiconductors that describe the fundamentalproperties, mobility, and recombination processes inherent to that material.

The system of equations solved by DEVICE admits both a steady-state and time-varyingresult. By enforcing the condition

0t

p

t

n

in the continuity equations, the carrier density and electrostatic potential can be solved atsteady-state. Steady-state simulations can be used to examine the system’s behavior at afixed operating point, and are also useful when extracting small-signal parameters for acomponent (e.g. for frequency response analysis). Alternately, by specifying an initialcondition for the carrier density and electrostatic potential, the equations can be solved in asequence of discrete times. The time-dependent behavior of the component can then beused to directly evaluate its large-signal time-domain response or extract large-signal ACparameters.

Boundary conditions are very important in an accurate semiconductor device simulation.Two categories of boundary condition are present in DEVICE: those that relate to theelectrostatic potential (Poisson’s equation) and those that relate to the carrier densities(the drift-diffusion equations). Poisson’s equation and the drift-diffusion equations aresecond-order partial differential equations (PDE), and each requires that the solution beexplicitly specified for at least one location. This is known as a Dirichlet boundarycondition. For the electrostatic potential, the Dirichlet condition takes the form of aboundary (internal or external) with a fixed voltage specified,

1)( VxV

as is typical of an electrical contact. For the carrier densities, the majority carrierconcentration is set to its equilibrium value at the interface between a contact and thesemiconductor, such that

0Cnp

At internal boundaries between two domains that are not contacts, the boundary conditionsare determined from the physical properties of the interface. In the case of the electrostaticpotential, the electric flux density must be continuous across the boundary in the absenceof a surface charge. For the electron and hole densities, boundary conditions between the

Reference Guide28


semiconductor and adjacent materials may be specified in terms of a surfacerecombination current density, which will default to zero (no carrier flux across theboundary) for insulators or an infinite recombination velocity (forcing the carrier density toits equilibrium value) for contacts. At the external (open) boundaries of the simulationdomain, homogenous Neumann boundary conditions are applied: the electric field normal tothe boundary is set to zero as is the surface recombination current density. Physically, thiscorresponds to an insulating boundary across which no charge can flow.

By convention, the length units in semiconductor models are chosen to be centimeters.This is reflected in the semiconductor device literature, and in the parameter coefficients forthe material models. Energies are calculated in electron Volts (eV), where the electronenergy E is related to the local electrostatic potential (voltage) as E = -qV. All energies(and voltages) are referenced from the (equilibrium) Fermi level of an electrical contact inthe system.

2.5.2 Meshing in DEVICE

DEVICE uses an unstructured, finite-element mesh, like the one shown in the followingscreenshot. The solution to the system of equations used to determine the physicalquantities of interest is estimated from the discrete formulation of those equations.Consequently, it's important to understand that of the fundamental simulation quantities(material properties, geometry information, electrostatic potential, and carrierconcentrations) are calculated at each mesh vertex.

A finer mesh (with shorter edge lengths and smallerelements) will better approximate the exact solutionto the system of equations, but at a substantial cost.As the mesh features become smaller, the simulationtime and memory requirements will increase. DEVICE provides a number of tools, including theautomatic and guided mesh refinement, that allowyou to obtain accurate results, while minimizingcomputational effort.

CAD layout editor 29


3 CAD layout editor

The image below shows a typical Lumerical CAD Layout Editor. This tool is used to setupand analyze all simulations, and to run all script files.

In this screenshot,different regions of theCAD in Layout modeare highlighted. Theyinclude:

Main title barToolbarsView portsObject TreeOptimization andSweepsScript Prompt

The Layout Editor has two modes of operation: Layout mode and Analysis mode. Layoutmode is used to setup your simulation. Simulation objects can be added, modified anddeleted in this mode. After a simulation runs, the Layout Editor automatically switches toAnalysis mode. In analysis mode, it is not possible to edit the simulation objects, sincewe want the object settings to match the data from the simulation. To edit simulation

objects, switch back to layout mode with the button.

3.1 Main title barThe menus on the main title bar are listed below. If any of the options can be selectedusing a button on a toolbar, the icon is drawn to the left of the name. Similarly, shortcutkeys are located to the right.

File The file menu includes options to create, save and load simulation files. The Import menuallows users to import structural data stored in GDSII files files.

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EditThe edit menu allows users to undo/redo their actions, and to copy/paste/edit object in thesimulation.

ViewThe view menu provides options to control the layout and visibility windows and toolbars.

SettingThis setting menu contains options to change the unit setting within the graphical interface. These option only apply to the GUI. Scripts always use SI units.

Simulation This menu contains settings for configuring resources and running simulations.

HelpThe help menu provides links to local PDF copies of the product documentation and linksto the larger set of online documentation, as well as options for checking which version of the software is installed.

3.2 ToolbarsThe following sections describe the various toolbars. Toolbars visibility can be controlled inthe View - Toolbars menu.

3.2.1 Main

The main toolbar contains buttons to add various Simulation objects, open the Materialdatabase and import files, as described below. When available, clicking the arrow to theright of the icon expands a drop-down menu containing related buttons. If one of the relatedbuttons is pressed, it replaces the default button in the toolbar. See the Simulation objectschapter for information about specific objects.

Material Database This button opens material database window. For more information, see the Materialdatabase chapter.

StructuresThis button will insert the shown structure primitive into the simulation. Pressing the arrowwill show all available primitives.

42

42



GroupsThis button will add an analysis, container or structure group into the simulation. Pressingthe arrow will allow selection of which group to add.

SimulationThis button will insert simulation or mesh override regions. Pressing the arrow will allowselection of which simulation object to add.

ImportThis button will open a window for importing files from other programs. Pressing the arrowwill allow selection of which kind of import.

DopingThis button will insert various doping regions into the simulation. Pressing the arrow willallow selection of which monitor to add.

GenerationThis button will insert various generation rate objects into the simulation. Pressing thearrow will allow selection of which monitor to add.

3.2.2 Edit

The edit toolbar contains tools used to copy, delete, or modify settings of simulationobjects.. When applicable, the shortcut key used to run the function from the keyboard isgiven in brackets next to the name of the tool. An object must be selected in order to usethese tools.

Edit properties (E) This command opens the edit properties window. See the Simulation objects chapter forinformation about specific properties for each object.

Tip: Group edit of multiple objects

Reference Guide32


The properties of multiple structure objects can be edited together by selecting multipleobjects prior to entering edit mode. This option is only available for structure objects, notsources or monitors. Any properties which are identical between all of the selectedobjects results in the common value being displayed in the edit dialog box.

Duplicate (D)This command makes a duplicate of the currently selected object. The copies that arecreated are identical to the originals, apart from a one grid cell offset in their x positionwhich allows the user to distinguish between the original and the copy. When multipleobjects are selected, all of the selected objects will be copied. When copying sources andmonitors, it is important to rename the copies so that each object has a unique name.

MoveThe move command allows shifting a single or multiple selected objects by a specifieddistance in each of the x,y,z dimensions. A pop-up window appears with field entries tospecify the shift amount.

ArrayThe array command allows the user to create an array or arrays of objects.

The array edit window that pops up contains several properties :A1 LATTICE: the distance between adjacent elements in the a1 directionA2 LATTICE: the distance between adjacent elements in the a2 directionANGLE BETWEEN A1 AND X-AXIS: the angle (in degrees) between the a1 direction andthe x-axisANGLE BETWEEN A1 AND A2: the angle (in degrees) between the a1 and the a2directions. COLUMNS, ROWS: the number of rows and columns that comprise the array.AZ LATTICE: the distance between adjacent elements in the z direction (valid for 3Dsimulations only)LAYERS: the number of elements in the z direction (valid for 3D simulations only)

The parameters in the edit window below produce the resulting array shown in the diagram.



Delete (Del)The delete command removes the currently selected object, or objects, from thesimulation.

3.2.3 Mouse mode

The mouse mode allows you to control the behavior of the mouse. Depending on themode, the user can edit objects, pan or zoom in the view ports or measure the distancefrom one point to another. When applicable, the shortcut key used to run the function fromthe keyboard is given in brackets next to the name of the tool. Only one mouse mode maybe selected at a time.

Select (S)This function puts the mouse into the select mode. This allows objects to be selectedthrough the view ports (objects may be selected in the objects tree regardless of whetherthe mouse is in select mode or not).

For reference, the current location of the mouse within the view ports is shown in the field atthe bottom right-hand corner of the CAD window (see the image below). The < and >buttons at the right decrease or increase the number of decimal places shown.

Changing aspect ratio settingsA feature available when in the select mode is changing aspect ratio settings. Right clickin one of the view windows to see the menu, and then select Change aspect ratiosettings.

Zoom (Z)

Reference Guide34


This function sets the mouse to be in the zoom mode. The default aspect ratio of the XYview and perspective views are locked at 1:1, which means circles always appear round(rather than as ovals). The aspect ratio for the XZ and YZ is not locked. Use the left clickto zoom in and the right click to zoom out. To zoom to a particular area, drag diagonallyacross the desired region. Finally, double clicking either button zooms to extent. Toadjust the view, it's easiest to set the XY view first, then adjust the Z view in the XZ or YZviews.

Pan view (P)The pan view mode allows the user to drag the view in the plane of the view port. In thePerspective window, the pan mode is used to rotate the view.

Scrolling in the view portsThe other method of adjusting the view ports is by using the arrow buttons on yourkeyboard. Each press of a button results in the view shifting in the direction indicated bythe arrow.

Ruler (R)Once the ruler mode is selected, a distance measurement can be made by pressing theleft mouse button and then dragging the mouse. A non-permanent triangle is drawnbetween the locations where the mouse button was pressed (A) and released (B). Thedistances are given in the lower left-hand corner of the CAD window (see the image below).The dx and dy fields correspond to the horizontal and vertical distance between A and B,and the AB field corresponds to the length of the hypotenuse.

3.2.4 View

The view toolbar contains tools to zoom to the extents of objects, edit grid settings andview the mesh used for the simulation. When applicable, the shortcut key used to run thefunction from the keyboard is given in brackets next to the name of the tool.

Zoom Extent (X)Selecting this tool centers and scales the view ports around the selected simulationobjects. For instance, pressing zoom extent while a structure is selected arranges theview such that only the structure are shown, while other simulation objects may appearoutside the extent of the view. When no objects are selected, pressing this button zoomsto the the largest object in the model. This function is also accessed via double-clickingeither the left- or right-hand mouse button while in zoom mode.



Drawing GridClicking on the drawing grid brings up a window in which the following options can beedited:

SHOW GRID: when checked, the grid will be plotted in the drawing paletteSNAP TO GRID: when checked, objects can only be moved so that their centers alignwith intersection points of the gridA1 LATTICE: the distance between grid lines in the a1 directionA2 LATTICE: the distance between grid lines in the a2 directionAZ LATTICED: the distance between grid lines in the z directionANGLE BETWEEN A1 AND X-AXIS: the angle (in degrees) between the a1 direction andthe x-axisANGLE BETWEEN A1 AND A2: the angle (in degrees) between the a1 and the a2directions

Recalculate simulation mesh (F5)Mesh generation is too computationally intensive to be done constantly as the simulationsetup is modified. If you wish to see the current mesh, use this option to update andrecalculate the mesh. The mesh is always recalculated before running a simulation.

3.2.5 Simulation

The simulation tools are:

ResourcesOpens the resource configuration manager. This window can add/remove and enable/disable computational resources. It also contains a useful configuration test tool to checkthe resource setup.

RunRun the current simulation. For more information on how to run simulation, see Running asimulation.

Run scripts This function will allow the user to run a Lumerical script file (*.lsf) to perform automated

commands such as plotting and saving data. This button is located in the CAD environmenttwice if the script editor is open: once in the simulation toolbar and once at the top of thescript editor. Pressing the button on the toolbar brings up an open file dialog. Pressing thebutton in the script editor runs the script that is selected in the editor window.

Reference Guide36


Switch to layout editor This function returns the simulation environment from analysis mode back to the layouteditor mode. If you switch to layout editor and then save the file, the data from thesimulation will be overwritten and lost.

3.2.6 Search bar

The search toolbar can be used to quickly search for topics in the online productdocumentation knowledge base. This will bring up the search results in a new tab in yourdefault browser.

Online help toolbarSearch the online knowledge base for the specified term. Requires internet connection. Ifan internet connection is not available, some product documentation is available in the Help- Reference Guide menu.

3.3 View portsThe view ports show a graphicalrepresentation of the simulation froman XY, XZ, YZ and 3D perspectiveview.

Depending on the current mousemode, the mouse pointer will eitherhave the shape of an arrow (select),a hand (pan), a magnifying glass(zoom) or a ruler (measurement).You can toggle between theseoptions with the mouse modetoolbar. When objects are selected,the vertices are drawn with redsquares (also, the object will behighlighted in the Object tree. It ispossible to copy and paste selectedobjects between different CADwindows using the standard Ctrl+Cand Ctrl+V shortcut keys.



3.4 Object TreeAs previously discussed, a simulation requires thatthe user define a set of objects, simulation region,sources and monitors. As a complete setup maycontain a large number of objects, the object tree wasdesigned to allow for organization and easy selection. All simulation objects are within the group, model,which represents the current simulation. Within'model', objects are listed as they are inserted by theuser. Press F2 or double-click to change the name.

To move the objects up and down the tree as well as into groups, we use the orange arrowsat the top of the window. The up and down arrows shift the objects relative to each other,while the left and right arrows move them out of and into groups. To add groups, we usethe button called groups in the main toolbar. Structure groups can only contain structuresand likewise, analysis groups can only contain monitors. See the online user guide sectionfor more information and examples about Structure groups and Analysis groups. The thirdgroup, "Containers" act like folders and can hold any type of object. In the image above,the 'Sources/Monitors' container group has both individual sources and monitors as well asan analysis group.

Note that there are buttons with green crosses at the top of the objects tree. These buttonscan be used to hide or display certain types of objects. When objects are selected, theyare highlighted blue in the objects tree and the vertices are marked with red squares in theview ports. Objects can always be selected by left-clicking on their name in the object treeor edited by right-clicking. Using the tree is the preferred method of selection especially incomplicated simulation setups with many overlapping elements. In the image above, thepower monitor, above, is selected.

3.4.1 Enable/Disable Simulation Object

User can enable/disable simulation objects by right-clicking on each and selecting"Enable/Disable". Disabled simulation objects will remain in the object tree (and can be

Reference Guide38


re-enabled), they will have no effect on the simulation.

See alsosetnamed , set

3.5 Results ViewSee the Results View section of the Reference Guide for more information.

3.6 Optimization and SweepsSee the Optimization and parameter sweeps section of the Reference Guide for moreinformation.

3.7 Script Prompt and Script EditorThe scripting language is useful for setting up complex structures and advanced dataanalysis. See the Scripting chapter for a list of all the script commands, as well asexamples on how to use them.

By default the script editor is located on the right hand side of the view ports and sharesthe same frame as the analysis window. When both windows are open, it is possible totoggle between the two through tabs located at the right side of the frame. The script fileeditor contains buttons to create, open, save and run script files. When multiple script filesare open, pressing on the run script button runs the one in the forefront. Note that whenentering scripting code in the script file editor, each command must be followed with asemicolon.

When running a script file in the a different directory using the GUI, the current workingdirectory is unchanged, but the directory of the script file is added to the scripting path.This way, any files called by that script will be found. However, the search order is thecurrent directory first, then any other folders in the path, and then the directory of the scriptfile.

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By default the script prompt islocated at the bottom of the CADwindow. Script commands areexecuted as soon as the ENTERbutton is pressed on the commandline. If a semicolon is missing at theend of the command line, it isautomatically inserted it for you.Multiple lines can be pasted into thescript prompt, and will run as in thescript editor. In this case though,only the last semicolon can beneglected.

3.8 Script Workspace and Script FavoritesSee the Script Workspace and Script Favorites section of the Reference Guide for moreinformation.

3.9 Changing the CAD layoutThere are pre-defined CAD layouts that can be accessed through main title toolbar. Changebetween the default layouts by selecting the drop-down menu VIEW->SET DEFAULTLAYOUT, and choosing one of them. In addition, have control over hiding and dockinglocation of the the windows and toolbars. The current layout is saved when CAD closes sothe next time the program is opened, your previous layout will be used.

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Reference Guide40


Hiding/showing windows andtoolbarsThere are two methods to hide orshow windows and toolbars1) In the main title toolbar selectVIEW->WINDOWS or VIEW->TOOLBARS. The visible windows/toolbars have a check mark next totheir name; the hidden ones do not.2) By clicking the right buttonanywhere on the main title bar or thetoolbar, the following pop up menuwill show up. As before, checkmarks indicate when windows andtoolbars are visible.

Moving and undocking windowsWindows can be undocked bydouble clicking the name with theleft mouse button. This isparticularly useful when you want tomake the script file editor windowlarger. Non-view-port windows canbe docked on top of each othereither to the right or to the left of theview ports. If they are placed on topof each other, tabs on the sidesallow toggling between them.

Tip: To reposition an undockedwindow on Linux, hold down the Altkey before attempting to move thewindow.

Moving toolbarsTo move a toolbar, hover the mouse over the top of the toolbar, where the dotted line is.When the mouse cursor becomes a four-headed arrow, press the left mouse button and



drag-and-drop the toolbar. If you reach a region where you can place a toolbar, the CADenvironment makes room for the toolbar indicated by a blue void.

Reference Guide42


4 Material database

This chapter explains the Material Database. See the following pages for details. Usersmay also find the Material modeling recorded video to be helpful.

Material databaseThe Materials Database allows for the definition of complex materials using experimentaldata or parametrized models. It can be accessed by clicking the material database buttonon the Structures tab. The Material Database stores the material data to be used in thesimulation. It also provides an interface to change material properties like color, meshorder, and model parameters. Experimental data can also be loaded into the database. Toview the resulting index profile, use the Material Explorer.

Electrical modelsSee this section for information on the available material models; insulators,semiconductors, and conductors.

Mesh orderSee this section for information on the mesh order property, which defines the meshingbehavior (priority) for overlapping objects.

4.1 Material databaseThe Materials Database allows youto manage (create, modify, delete)the materials that are available foruse in your simulations. A copy of the database is stored ineach simulation file. A change tothe database in one file does notautomatically change the materialsin any other files. To modify thedefault materials that appear whenyou create a new simulation, editthe simulation file in the Defaultssubdirectory of the installationdirectory.

Import / ExportThe import and export buttons allow you to transfer material data between simulation filesvia Material Database Files (.mdf) files.

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54

http://www.lumerical.com/support/courses/fdtd_material_modeling/video.html

Material database 43


Material list The material list shows the materials stored in the material database. A number ofmaterials are provide with the product installation. To create additional materials, use theAdd button. You can also modify some of the material properties (name, color, meshorder, etc) in the list view.

Default materials provided with the product installation are write protected, and can not bedirectly modified. To modify the properties of a default material, simply use the Copybutton to duplicate the material. The copy will be unlocked. The first column of the listshows which materials are write protected.Materials currently used in the simulation can not be deleted. The second column of thelist shows which materials are in use. To delete these materials, first modify the simulationso they are not used.

Material PropertiesUse the Material properties window to view and edit the material model parameters. Formodel parameter definitions, see the material models section.

4.2 Electrical modelsThis section describes the electrical material models supported by the Material Database. Model parameters can be edited in the Material property panel of the Material Databasewindow. Materials are categorized by their physical characteristics. The three types ofsupported materials are conductors, insulators, and semiconductors.

ConductorMaterials that are defined as conductors are treated as ideal electrical conductors inDEVICE: they are assumed to have zero resistivity. Consequently, the internal electric fieldmust be zero, and the voltage applied to the conductor will be constant across its domain.Materials specified as conductors will be treated as ideal electrical contacts in thesimulation.

See more detailed information on Conductors .

InsulatorMaterials that are defined as insulators are treated as ideal electrical insulators in DEVICE:they are assumed to be perfect dielectrics without free charge.

See more detailed information on Insulators .

SemiconductorSemiconductors, like insulators, are band gap materials. The band gap of a semiconductoris typically small enough to allow a significant fraction of electrons to be thermally excited

44

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Reference Guide44


from the valence band to the conduction band at room temperature (300K). The band gapfor a semiconductor typically ranges from 0.5-1.5eV. When energetically excited to aconduction band state, electrons leave behind a positively charged mobile vacancy, knownas a hole, which behaves much like a free electron in the semiconductor. The mobility ofthe electrons and holes and the rates at which they are generated and recombine aredetermined by the models described in this section.

See more detailed information on Semiconductors .

4.2.1 Conductors

Conductor Fundamental PropertiesWork FunctionThe defining characteristic of the conductor is its work function, which describes the energycost of removing an electron from the material.

4.2.2 Insulators

Insulator Fundamental PropertiesRelative Dielectric PermittivityThe relative permittivity (or dielectric constant) of the material is equal to the square of therefractive index, and is assumed to be the DC (zero frequency) value.

4.2.3 Semiconductors

In This Section:Semiconductor Fundamental PropertiesMobility Bulk Recombination and GenerationSurface RecombinationReferences

Semiconductor Fundamental PropertiesRelative Dielectric PermittivityThe relative permittivity (or dielectric constant) of the material is equal to the square of therefractive index, and is assumed to be the DC (zero frequency) value.

Work FunctionIn a semiconductor, the work function φs describes the energy cost of removing an electronfrom the intrinsic energy level (the Fermi energy of the undoped semiconductor) and placingit at "infinity." A related value is the electron affinitiy χs, which is the energy cost ofremoving an electron from the conduction band edge.

44

44

46

50

53

54



V

CBGiss

N

NTkEln

22,

where EG is the band gap and NC and NV are the effective density of states in theconduction band and valence band, respectively.

Effective MassTo account for the influence of the crystal lattice potential of the semiconductor, electronsand holes can be approximated as free charges with an effective mass (relative to theelectron rest mass) that depends on the electronic band-structure of the material. InDEVICE, the effective mass is treated as a parameter of the material model.

The temperature variation in the effective mass can be accounted for with a quadraticmodel

2*,

*, )0()( TTmTm pnpn

where coefficients α and β, and the effective mass at T=0K are inputs to the model.

Related to the effective mass is the effective density of states in the conduction andvalence bands

2/3

2

*22

h

TkmN Bn

C

2/3

2

*22

h

TkmN

Bp

V

where h is Planck’s constant.

Band GapA key physical property of the material is the band gap, which, like the effective mass, isderived from the electronic band-structure of the material. In DEVICE, the band gap energyis treated as a parameter of the material model.

The temperature variation in the band gap can be accounted for with a "universal" empiricalmodel

T

TETE GG

2

0,)(

where coefficients α and β, and the band gap energy at T=0K are inputs to the model.

Band Gap Narrowing

Reference Guide46


When impurities are added to the intrinsic (pure) semiconductor, localized allowed energystates may be introduced at energies that lie within the band-gap. In the case of dopants,these impurity states will exist with energies near the conduction or valence band edges(such that the dopants readily ionize at moderate temperatures). When the concentration ofdopants is large, these discrete states will begin to merge and form a thin "band" of allowedstates within the band gap, effectively narrowing the band gap. This can be viewed as anarrowing of the band gap or an increase in the effective density of states.

The Slotboom model1 for band gap narrowing is provided in DEVICE to account for thiseffect,

CN

NN

N

NNVE ADAD

G

0

2

0

1 lnln

where the coefficients V1, N0, and C are inputs to the model, and the effect can bespecified independently for electrons and holes. Note that the sign implies a narrowingeffect for positive coefficients.

Intrinsic Carrier ConcentrationThe intrinsic carrier concentration is calculated from the effective mass and band gap, andis only displayed in the Material Database for reference. It is calculated as

TkENNn BGVCi 2/exp

where T=300K is assumed, and the effective density of states and band gap are treated aretreated as intrinsic quantities (before band gap narrowing).

MobilityThe mobility parameter in the drift-diffusion equations is the physical link between themotion of carriers (electrons and holes) and the semiconductor material. The mobility canbe viewed as a measure of how readily electrons and holes can move through the crystallattice of the semiconductor. In the absence of any interactions with the lattice, impurities,or other carriers, electrons and holes would move freely in the periodic potential of thelattice; interactions that change the momentum of the carriers are termed scatteringevents. Different types of scattering contribute to the mobility of the electrons and holes,including

lattice scattering,ionized and neutral impurity scattering, andcarrier-carrier scattering.

In addition, the velocity of the carriers is observed to saturate at high-fields. Each of thesescattering mechanisms can be addressed in DEVICE by applying the appropriate models,which are detailed in the following sections.

Lattice Scattering

54



The fundamental process that impedes the free motion of the carriers in the lattice isthermal scattering off of the lattice itself. The mobility due to lattice scattering is treated asa basic input into the DEVICE semiconductor model, and may be entered as a constantvalue or with a temperature dependence described by the "universal" temperature model,

300)300()(

TATA

where A(300) is the value of the parameter at T=300K, and η is a temperature exponent. In

the case of the lattice scattering mobility µ L, the temperature dependence reads

300)300()( ,,

TT L

pnL

pn

.where subscripts n and p refer to electrons and holes, respectively.

Impurity and Free-Carrier ScatteringMany models exist to account for the influence of impurities on the carrier mobility.DEVICE provides support for three common models with wide-ranging applicability: the

Caughey-Thomas model2 , the Masetti model3 , and the Klaassen model4 . Eachmodel requires a variety of coefficients; default values are provided with DEVICE forcommon semiconductors.

For general modeling purposes, the Caughey-Thomas model or Masetti models are oftensufficient, and coefficients are available for multiple semiconductor materials. The Klaassenmodel is primarily tuned for silicon at T=300K, and coefficients for other materials are notavailable. At moderate doping densities, the mobility predicted by all models reduces tothat of the Caughey-Thomas model.The most basic model is the Caughey-Thomas model,

ref

pnL

pn

pnLI

pnNN /1

min,,min

,,

where N is the total doping concentration (N = NA + N

D), µ L is the lattice scattering mobility

(as determined from the model chosen in the previous section), and µ min, Nref, and α aretemperature-dependent coefficients described the universal temperature model.

To account for extremely large doping concentrations, the Masetti model can be selected,which adds a correction to the Caughey-Thomas model for large N:

NCCN s

pn

r

pnL

pn

pnLI

pn/1/1

)2(,

min,,min

,,

.

Again, N is the total doping concentration (N = NA + N

D) and µ L is the lattice scattering

54 54 54

Reference Guide48


mobility. Parameters µ min, µ (2), Cr (replacing N

ref of the Caughey-Thomas model), C

s, α,

and β are each temperature-dependent coefficients described the universal temperaturemodel.

Finally, the mobility model proposed by Klaassen can be used to account for theaforementioned doping effects (at moderate and high impurity concentrations), as well asthe influence of carrier-carrier scattering. The Klaassen model combines the basic latticescattering with the impurity and carrier-carrier scattering using Matthisen’s rule

ICpn

Lpn

LICpn ,,,

111

where µ L is the lattice scattering mobility and µ IC is Klaassen’s impurity and carrier-carrier(IC) scattering mobility. The formulation of the IC scattering mobility is complex andinvolves multiple levels of coefficients and models accounting for

majority carrier scattering by dopants,minority carrier scattering by dopants, andelectron-hole scattering.

To begin, the IC mobility is defined as a function of the dopant and carrier concentrations,

..,

min,,

min,,

,

1

..,

,

min,,

2,

, ,,,effscpnpn

Lpn

pnL

pn

scpn

ref

effscpn

scpn

pnL

pn

Lpn

ADIC

pnN

pn

N

N

N

NpnNN

where µ L is the lattice scattering mobility, and coefficients µ min, Nref 1

(equivalent to Nref

or C

r), and α are defined as for the Caughey-Thomas or Masetti models. Note that the Klaassen

model accounts for temperature dependence separately, therefore constant a constantvalue should be used for the lattice scattering mobility.

In the preceding equation, the "scattering densities" are

nNNN

pNNN

DAscp

ADscn

where the donor and acceptor densities, ND and N

A respectively, are corrected according to

the clustering function:

2

,

2

,

/

/

AArefA

AAA

DDrefD

DDD

NNC

NNN

NNC

NNN



Here, CD, N

ref ,D, C

A, and N

ref ,A are coefficients of the model.

The "effective scattering densities" are defined as (using the same clustering-correctedacceptor and donor concentrations)

p

DpAeffsc

p

n

AnDeffsc

n

PF

nNPGNN

PF

pNPGNN

..

..

The function G describes the ratio of scattering cross-sections between repulsive andattractive screened Coulomb potentials as a function of the factor P (itself a function ofcarrier density and majority dopant density). The factor P accounts for the screening effect,and is calculated as the weighted harmonic mean of two parameters accounting for thefree-carrier and ionized impurity screening,

1

,,

1

,,

,

,

pP

f

NP

fpNP

nP

f

NP

fnNP

pBH

BH

ApCW

CWAp

nBH

BH

DnCW

CWDn

Weights fCW

and fBH

are coefficients of the model.

The same factor P is used in the calculation of the function F, which describes the mobilityratio between stationary, infinite-mass secondary scatters (e.g. ionized impurities) andmobile, finite-mass secondary scatters (e.g. free carriers). Both functions F and G areparameterized fitting functions to physical processes, and the coefficients of thosefunctions (r

1 to r

6 for function F and s

1 to s

7 for function G) are also coefficients of the

model.

High-Field SaturationAs the electric field within the semiconductor increases, the drift-velocity of the carriers iscommonly observed to saturate, reducing the mobility accordingly. To account for thiseffect, DEVICE includes a saturation velocity mobility model

satpn

pnLIC

pn

LICpnLICE

pn

v ,

,,

,

,

1

where µ LIC is the mobility accounting for lattice, impurity, and carrier-carrier scattering (as

Reference Guide50


calculated using the active models for those processes) and vsat is the model coefficient

that determines the saturation velocity. The product of the low-field mobility µ LIC and thegradient of the quasi-Fermi level is equivalent to the velocity in the context of the drift-diffusion equations.

Bulk Recombination and GenerationRecombination describes the processes by which an electron from the conduction bandmakes an energetic transition and neutralizes a hole in the valence band. Generationdescribes the complementary behavior, where an electron is excited from the valence bandto the conduction band, creating a hole in the process (often, the term electron-hole-pair isused when referring to generation). The models for bulk recombination and generationprocesses relate to the physical mechanisms by which the carriers make the energetictransition. DEVICE provides models describing

trap-assisted (Shockley-Read-Hall) recombination,Auger recombination, andradiative recombination.

These models and their parameterizations are the subject of the following sections.

Trap-Assisted (Shockley-Read-Hall) RecombinationThe recombination process in the trap-assisted model assumes that there are unoccupied"trap" states (also referred to deep-level defect states) within the band gap. Typically, thesestates result from impurities (either intentional or unintentional), and the most active haveenergy levels near the middle of the band gap. Recombination occurs when an electronrelaxes (transfers energy to the lattice or emits a photon) to the trap state from theconduction band, and sequentially, a hole from the valence band relaxes to the same trapstate. This process is modeled using the Shockley-Read-Hall (SRH) equation,

11

2

ppnn

nnpR

np

iSRH

where τn and τ

p are the electron and hole lifetimes, respectively, and n

1 and p

1 are the

effective densities of carriers in the trap states. The trap states are characterized by theirdensities N

t, capture cross-section σ

t, and energy level Et - Ei (commonly abbreviated as

Et and referenced to the intrinsic energy level). The constants n1 and p

1 are calculated as

TkEie

TkEie

Bt

Bt

enp

enn/

1

/1

The carrier lifetime can be determined from the capture cross-section and trap density as1

*,

,,

3

pn

Btpnpn

m

TkN



but is commonly taken as an input to the model.

DEVICE provides a temperature dependent model for the SRH carrier lifetime, as well asmodels that include corrections for doping density. The basic temperature-dependent modelfor the carrier lifetime follows the usual power-law relation

pnTT srh

pnsrh

pn

,

300)300()( 0,

,0,

,

Alternately, a constant value can be supplied for both electrons and holes.

To account for doping concentration effects, DEVICE provides two correction models thatuse the previous expression for the SRH carrier lifetime as an input. First, a modified modelin the form proposed by Fossum is described by

refpn

DApn

pnpnpnpnpn

srhpnsrh

pnN

NNN

NN pn

,

,

,,,,,

0,,

, where,,

The original model of Fossum can be obtained by setting coefficients α, β, and σ to one (1)and setting γ to zero (0), and this is the default model used in DEVICE.

Alternately, a formulation proposed by Klaassen can be selected, where the SRH carrierlifetime correction is given by the equation

refpn

DApn

pnsrh

pnpn

srhpnsrh

pnN

NNN

T

N

pn

,

,

,0,

,,

0,,

, where,3001

,

Note that this model explicitly includes the temperature dependence, and should only beused in concert with a constant value for the baseline SRH carrier lifetime.

Auger RecombinationAuger transitions are three-particle transitions (two carriers scatter and transfer energy and/or momentum to a third carrier) that describe four related processes, which are illustrated inthe figures below. Each process has an associated rate coefficient. According to theprinciple of detailed balance, the net rate for each type of carrier must be zero atequilibrium, such that

AUepi

AUcp

AUeni

AUcn CnCCnC 22 and

Assuming that the value of the rate coefficients does not change as the system moves fromequilibrium, the net Auger recombination rate is

2i

AUcp

AUcnAU nnppCnCR

Note that Auger transitions depend only on carrier density, differentiating them from otherrecombination processes.

Reference Guide52


Recombination byelectron excitation

Recombination by holeexcitation

Generation byelectron relaxation

Generation byhole relaxation

pnCR AUcn

AUn

2 2npCR AUcp

AUp nCG AU

enAUn pCG AU

epAUp

DEVICE supports three models for the capture rate coefficients, includingthe universal temperature model proposed by Klaassen,an empirical model by White accounting for a reduction in the recombination rate at highcarrier concentrations, anda model by Clugston and Basore accounting for both high and low injection conditions.

The universal temperature model proposed by Klaassen takes the usual power-law form,

pnTCC pnpn

,

300)300(,

0,

and is suitable for devices where Auger recombination is moderate (low injectionconditions). The Auger rate coefficients are only weakly dependent on temperature, andconstant values may be used as well.

An alternate empirical model proposed by White can be used as a correction to theprevious model, taking that coefficient as an input. The White model accounts for thereduction in the Auger recombination rate observed at high carrier densities (due to strongscreening effects), and is expressed as

p

CC

n

CC

p

pn

n1

,1

00

where the coefficient α determines the transition density.



A related model proposed by Clugston and Basore is designed to account for the tworegimes related to minority carrier injection:

nN

nC

nN

NCC

pN

pC

pN

NCC

A

HIp

A

App

D

HIn

D

Dnn

2

2

0

0

DEVICE will use the Auger capture rate coefficient defined in the Klaassen model (or aconstant value) for the low injection conditions, and apply a second coefficient when strongminority carrier injection dominates according to the preceding formulations.

Radiative RecombinationIn a radiative transition, a conduction band electron will relax directly, emitting a photonwhose energy approximately equals that of the band gap, and then recombine with a holein the valence band. The opposite process occurs when a photon is absorbed by anelectron in the valence band, promoting it to the conduction band and leaving a hole in itsplace. Radiative recombination transitions are typically significant only in materials with anarrow bandgap, or a bandstructure that permits direct transitions in momentum (e.g.GaAs). Radiative recombination is typically negligible in bulk silicon.

The recombination rate is determined from the product of a capture rate coefficient and thecarrier density product,

npCR OPTcOPT

and the corresponding generation rate is simply the emission rate constant,OPTeOPT CG

Once again, the coefficients are related by the principle of detailed balance at thermalequilibrium, such that

2i

OPTcOPT nnpCR

The optical capture rate coefficient can be modeled in DEVICE either as a constant orusing the universal temperature power-law,

300)300()(

TCTC OPT

cOPTc

Surface RecombinationTrap-Assisted ModelLike bulk Shockley-Read-Hall (SRH) recombination, the presence of deep-level trap states

Reference Guide54


at the semiconductor surface catalyzes recombination. The surface recombination processis modeled by a formula similar to that of the bulk case,

s

n

s

p

isurf

pps

nns

nnpR

11

2

11

but differs slightly from the bulk process since it is occurs on a two-dimensional surface.The trap density N

ts is now given per unit area, such that the carrier lifetime of the bulk

case is replaced by a surface recombination velocity,

*,

,,

3

pn

Btspnpn

m

TkNs

The surface recombination velocity is treated as an input parameter in DEVICE, chosen toreflect the non-ideal nature of the material surface. The surface recombination velocity maybe temperature dependent. Like the bulk case, the constants n

1s and p

1s are calculated as

TkEies

TkEies

Bts

Bts

enp

enn/

1

/1

References1. Slotboom, J.W., Solid-State Electron., 20, 279 (1997)2. Caughey, D. M. and Thomas, R. E., Proc. IEEE, 52, 2192 (1967)3. Masetti, G., et al., IEEE Trans. Electron Devices, ED-30, 764 (1983)4. Klaassen, D. B. M., Solid State Electronics, 35, 953 (1992); Klaassen, D. B. M.,

Solid State Electronics, 35, 961 (1992)

4.3 Mesh orderThe mesh order property governs how overlapping objects are meshed in the simulation. Itserves no role for objects which do not overlap. The mesh order can be set at the materiallevel (in the material database), or the object object level (in the object properties). Materials with a lower mesh order take priority over materials with a higher priority number(i.e. order 1 takes priority over 2). Areas which overlap are assigned the materialproperties of the higher priority material (see the following figure).



In the figure to the left, there are twoobjects that partially overlap. Depending on their mesh orders, theobject that is actually beingsimulated will be different.

In the event that both overlapping materials have the same order, the mesh order will beinferred from the Object tree. Objects at the bottom of the tree will take priority over objectsat the top of the tree. To ensure your simulation is well defined, it is recommended thatyou avoid situations where two different overlapping structure have the same mesh order.

Tip: Plot the geometry after meshing to confirm that the structures was meshed asintended.

Reference Guide56


5 Simulation objects

There are several types of simulation objects inFDTD Solutions, MODE Solutions' propagator,MODE Solutions' Eigenmode Solver and DEVICE.

These objects are used to model the physicalstructure, define the solver region, any sources oflight or doping/generation regions as well asmonitors to collect data.

The following sections provide detailed descriptionsof each simulation object. Each simulation objectcan be added by clicking on the correspondingicon in the GUI.For example, in the screen shot on the right,

clicking on the button would add a circlephysical structure object.

Once the object is selected, pressing the EDIT button will bring up a window where itis possible to modify the properties of the simulation object. The corresponding window forthe circle object is shown below.

TIP: In-field equation interpreterThe fields for numeric parameters can be used as a simple calculator. For instance, if you

Simulation objects 57


wish to set a value to the square root of 3 divided by e, just enter sqrt(3)/exp(1) into thefield. For more information, see the Equation interpreter section.

Notes:Structure objects support Multi-object editing. If you select multiple objects then clickEDIT, you can edit properties that are common to all of the selected objects.Monitors and sources have some global properties that apply to many objects. Forexample, the global source frequency range can be applied to all sources. The global

properties can be edited with the GLOBAL PROPERTIES button.

GroupsSimulation objects can be organized into various types of groupings.

Container GroupA container group is the simplest type and can contain all object types as well as othergroups. This object acts like a simple folder allowing the user to collapse and expand itscontents in the object tree. Its only user setting is a position offset in x,y,z for allcontained objects.

Structure Group Structure groups are one step above container groups in that they allow scriptingcommands of structures properties. This group contains user-generated variables andscripts that can be utilized to edit and set up parts of the structure. For example, a scriptcan be set up to insert many circles to create a photonic crystal cavity of a certain shapeand size. See the Properties tab and Script tab sections for more information.Structure groups can contain other structure groups.

The purpose of this section of the Reference Guide is to describe all of the availablesimulation objects and their properties. This section is organized as follows. There are fivesubsections. The first four subsections correspond to the four types of object categories.Each of these sections begins with a brief overview of the simulation objects followed by adescription of their property settings. The properties are organized according to the tab thatthey are located in when the EDIT button is pressed. The last of the five subsectionsdescribes the syntax for the equation interpreter.

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5.1 StructuresStructures in a simulation interact with light/electrical sources to produce interestingeffects. They are split into 3 groups:

Structures (Primitives)These are the primitive shapes that make up all structure setups.

ImportsThese options open windows that can be used to import structure data from other sourcessuch as pictures or text files.

5.1.1 Primitives

The button includes options to to add the following primitive structures:

TriangleTriangular objects denote physical objects that appear triangular from above. For 2Dsimulations, these objects represent triangles while in 3D these objects are extruded in thez direction to a specific height. They are actually polygon objects, with the number ofvertices set to 3.

RectangleRectangular regions denote physical objects that appear rectangular from above. For 2Dsimulations, these objects represent rectangles while in 3D these objects are extruded to aspecific height.

Polygon Polygons allow the user to define a custom object with a variable number of vertices. Thelocation of each vertex can be independently positioned within a plane, and the vertices areconnected with straight lines. For 3D simulations, the object is extruded in the zdimension. In DEVICE, the vertices have to be entered in a counter clock wise manner forthe structure to be defined and meshed properly.



CircleCircles denote physical objects which appear circular or ellipsoid from above. They areeither circles/ellipses in 2D, or circular/ellipsoid cylinders in 3D.

RingRing regions represent physical objects that consist of full or partial rings when viewed fromabove. Rings in 3D simulations are extruded in the z direction to a specific height.

Sphere In 3D simulations, users can define spherical regions of constant refractive index throughthe spherical physical object. Spherical objects only exist in 3D simulations.

Pyramid Pyramids can be configured to half flat tops and/or flat bottoms, and either narrow orexpand in the vertical z direction. Pyramids are only available for 3D simulations.

5.1.2 Geometry tab

The geometry tab contains options to change the size and location of the structure.

5.1.3 Material tab

The material options are as follows:

MATERIAL: This field can be set to any material included in the material database. It ispossible to include new materials in the database, or edit the materials already included.See the material database section for more information.

OVERRIDE MESH ORDER FROM MATERIAL DATABASE: Select to override the meshorder from the material database and manually set a mesh order. The mesh order is usedby the simulation engine to select which material to use when two materials overlap. Seethe mesh order section for more details.

MESH ORDER: Set the mesh order in this field if the OVERRIDE MESH ORDER FROMMATERIAL DATABASE option is selected. If the option is not selected, the field displaysthe material's default mesh order from the database. For example, a material of meshorder 1 will take precedence over a material of mesh order 2.

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5.1.4 Rotations tab

Rotate objects by setting the following variables:

FIRST, SECOND, THIRD AXES: Select rotation axis. Up to three different rotations canbe applied. ROTATION 1,2,3: The rotation of the object in a clockwise direction about each axis,measured in degrees.

5.1.5 Graphical Rendering tab

The graphical rendering tab is used to change how objects are drawn in the layout editor.The options are:

RENDER TYPE: The options for drawing the objects are detailed or wireframe. Detailedobjects are shaded and their transparency can be set using OVERRIDE COLOROPACITY FROM MATERIAL DATABASE.DETAIL: This is a slider which takes values between 0 and 1. By default it is set to 0.5.Higher detail shows more detail, but increases the time required to draw objects. Thissetting has no effect on the simulation.OVERRIDE COLOR OPACITY FROM MATERIAL DATABASE: When unselected theopacity is determined from the material database. When selected, you can specify avalue for ALPHA between 0 (transparent) and 1 (opaque) for the object, depending onhow transparent you want the object to be.

5.1.6 Import Data tab

The button includes options to import from a variety of formats:

GDSIIThis file format is commonly used to store 2-dimensional geometric data. For details, see GDSII Import .

5.1.6.1 GDSII Import

The GDSII import function allows you to import structures from a GDSII file into the layouteditor. The GDSII file format is commonly used to store 2-dimensional geometric data. Thisdata can be directly imported into a 2D layout environment, or it can be used to import 3Dobjects into a 3D layout environment by extruding the 2D data in the Z dimension.

Characteristics of the GDSII file

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Lumerical products support most, but not all features of the GDSII file format. Unsupportedfeatures should not prevent the file from being imported, however, the results may not be asexpected. The following table details the supported and unsupported features.

Features Supported

General

Multiple cells in GDSII library file Yes

Layer numbers for drawing objects Yes

Primitives/Objects

Box/Rectangle Yes

Polygon Yes

Path (see note below) Yes

Node No

Text No

Symbolic cell reference Yes

Array cell reference Yes

Advanced

Cell references in external library/file No

Magnifications in array and symbolicreferences

Yes

Rotations and mirroring in array andsymbolic references

Yes

Note: Path cornersPath objects in GDSII files are piecewise linear lines plus a width and optionally someinformation on how to handle corners and ends. In general, GDSII files support severaltypes of corner style options (squared, rounded, extended squared, etc). Our importfunction supports type 0 (squared ends flush to the end-point) and will default to type 2

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(square ends with 1/2 the width added to the end-point) for all other types.

Note: Flattened GDSII filesWhile we do include scale, rotate, flip, and automatic flattening of references, not allfeatures of GDSII are currently supported. If you run into any problems, you may havebetter results by flattening the file first.

GDSII Import

Import using GUIGDSII import is initiated by accessing the IMPORT->GDSII option from the FILE menu, orby pressing the Import GDS button located on the main toolbar. This will bring up astandard file browser, which will allow you to select a file with the extension .gds or .db.Selecting a GDSII file will bring up the Single layer GDSII Import window as shown below.

The following 3 input parameters control how the GDSII data is imported:

Cell name: This selection menu contains the valid cells available in the GDSII library.Select the cell you wish to import.Layer number: This selection menu contains all of the layer number present in the GDSIIfile. Only structures with the selected layer number will be imported by this operation.Material: This selection menu contains a list of the valid materials in your currentsimulation environment. This material will be assigned to the imported structures.

Selecting the Import layer button imports all the structures with the selected layer numberin the selected cell into the layout environment. These structures are automatically inserted



into a structure group. The material is set as an input parameter for the structure code, andthe script in the structure group sets all the objects to the desired material. The name ofthe structure group includes the original number of layers. For 3D simulations, the structuregroup contains a variable "z span". This used to set the width of the layer in the z direction.The origin of the structures, as well as their orientation, can be changed by changing theproperties of the structure group.

Import using script commandThe GDSII file can also be imported via script, the command gdsimport can be used. For

more information of the script commands, please visit Reference Guide - GDSII chapter .

See AlsoUserguide - GDSII - Import and export

5.1.6.2 Surface import window

Options in the surface import window include:

After surface data has been imported, the Import data tab allows the following properties tobe modified:

IMPORT: You can import new data into the object, or clear the imported data via asimple GUI. For properties of the import GUI, see bottom of page.X,Y FINE SCALE ADJUSTMENTS: Re-scale the object X,Y span. Modifying theseproperties will change the X,Y span properties. Z SCALE property not used for surfaceimport.DATA SIZE: These properties provide some information about the imported data. Theyare read-only.LOWER, UPPER REF HEIGHT: Set the vertical location of the reference plane (height=0in the imported data). Modifying these properties will change the Z, Z span properties.

Note: Related propertiesIt is important to notice that the 'x, y scale' and 'x, y span' properties are linearly related. Doubling the object 'x span' will automatically double the 'x scale' property. Similarly, the 'lower, upper ref height' properties are related to the 'z and z span' properties,although the relationship is slightly more complex. See the following figure for details. Thesurface's can be truncated by setting the 'z span' property to a small value.

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Note: Overlapping surfacesIf the z span is small enough such that the upper and lower surfaces overlap (as shownbelow), no structure will be included in the simulation in that region.

For additional information and example files, see the Import object surfaces page in theUser Guide section of the Online help.

Import surface GUI settings:SELECT FILE: let the user specify the data file to be imported.X0, Y0, Z0: the data origin in the global coordinates of the Graphical Layout Editor.X,Y: This defines the span of surface that you are importing.INVERT X AND Y AXIS: It is often easy to invert the x and y axis when exporting the file.Selecting this checkbox means that the x and y axes are automatically reversed.UPPER SURFACE, LOWER SURFACE: Choose which surface is being imported.FILE UNITS: Select units for the data in your file.



5.1.7 Properties tab

The properties tab is only available for structure groups. The properties tab is used to setthe origin of the group, and to create the custom properties of the group that are the inputsof the group script. Custom user property variables may be added with the ADD button,and removed with the REMOVE button. Each user property has a name and a type(number, frequency ect). The user properties can be set manually in the edit GUI or throughscript commands. For more information and examples, see the Structure groups page ofthe User Guide section of the Online Help.

5.1.8 Script tab

The script tab is only available for structure groups. The script tab can contain scriptcommands that are used to set up a structure or edit the properties of structures locatedwithin the structure group. The structure group has access to the user variables defined inthe PROPERTIES tab, and can change properties of any objects that are contained in thegroup. The script does not have access to objects which are not located in the group, anddoes not share the same variable space as the script prompt.

The script is run every time the TEST or OK button is pressed, or when one of the userproperties is changed with a script command.

The following buttons and regions are available in the script tab:SCRIPT: This is where the script commands are written. To find a list of scriptcommands, see the Scripting Language section of the Reference Guide.TEST/SCRIPT OUTPUT: Press the TEST button to run the script. If there are no syntaxerrors in the script the SCRIPT OUTPUT will read <script complete>.

For more information and examples, see the Structure groups page of the User Guidesection of the Online Help.

5.2 SimulationSimulation objects are used to define simulation parameters like boundary conditions andmesh size.

Simulation regionThe simulation region defines most simulation parameters including the size and meshsize.

Mesh ConstraintThe mesh constraint region is used to override the default mesh element area in some partof the simulation region. Normally the meshing parameters are set in the Simulation

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region. However, if some specific meshing conditions are required in part of the simulationregion, a mesh constraint region can be specified. Note that only one simulation region per simulation is supported, but multiple meshconstraint regions may be used.

TIP: Objects which lie outside the simulation region.Any simulation objects contained or partly contained within the simulation region areincluded in the simulation, while any objects which fall completely outside of thesimulation region are not included in the simulation. Those physical structures (andportions thereof) lying within the simulation region are included in the simulation (i.e. thesimulation is performed on that portion of the physical structure lying within the simulationregion). Physical monitors and sources are treated in a similar fashion, such that anyportion of a monitor or source lying within a simulation region will be used. The user iswarned when at least one source or monitor falls completely outside the simulationregion.

5.2.1 General tab

The options in the general tab depend on whether the item being edited is a simulationregion or a mesh refinement region. Simulation regionThe simulation region contains several settings:

SIMULATION TEMPERATURE (K): The temperature in Kelvin at which the simulation willbe done.SOLVER GEOMETRY: This drop down menu gives the choice of a 2D simulation planeor a 3D simulation.NORM LENGTH: The length of the device in the direction perpendicular to the plane ofthe simulation; any normalizations length will be with respect to this value.SOLVER MODE: DC mode for dc simulations and transient mode for time dependantsimulations. The color of the simulation region will change depending on which option ispicked. Also, the available options in the contacts table will change accordingly.CONTINUE FROM PREVIOUS SOLUTION: If this option is checked, the user has thechoice to specify a file that has already been run with a solution. This solution will beused as the starting point for the Newton solver. In simulations where the starting pointisn't at zero volts, this can be very useful to save time.

.

Mesh Constraint region For the mesh constraint region, the maximum element area can be set.



5.2.2 Mesh tab

Global Mesh ConstraintsThe global mesh settings section contains several settings:

MAXIMUM EDGE LENGTH: The maximum length of an edge of a triangle (in 2D) used inthe mesh. MAXIMUM EDGE LENGTH: The minimum length of an edge of a triangle (in 2D) used inthe mesh. TRIANGLE QUALITY: The quality of mesh triangle, defined the minimum angle used inthe triangular mesh cells. The higher the angle, the higher the quality of the triangle

Auto Refinement SettingsThe auto refinement settings section contains several settings:

MAX REFINE STEPS: The automatic refinement proceeds in multiple stages, creating aquality triangulation and refining the mesh according to the change in doping density and,if present, optical generation rate. This setting limits the number of refinements at eachstage, and corresponds to the number of vertexes that can be added to the mesh at eachstage. SENSITIVITY: This setting controls the threshold at which the mesh will be refined due tothe gradient in the doping density or optical generation rate. The default value will roughlycorrespond to a limit of a factor of 2 change in the doping density or generation rate overthe span of an element in the mesh.

5.2.3 Geometry tab

The geometry tab contains options to change the size and location of the simulation ormesh refinement region.

5.2.4 Transient tab

Transient Simulation ControlsThe transient simulation controls section contains several settings:

MIN TIME STEP: The smallest time step that will be used in the transient simulation(used as the initial time step)MAX TIME STEP: The largest time step that will be used in the transient simulation.

Downsampling

DOWN SAMPLE MODE: The type of downsampling to use, None, for no downsampling,count, for specifying the number of point to downsample at, and interval to specify thedownsample step size.

Global Optical Shutter

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The global optical shutter will apply a shutter to all the optical generation objects in thesimulation. SHUTTER MODE: disabled, for no shutter, step on and step off for step functions, pulse onand pulse off for a pulse with on and off times. The time shutter function will be plotted asthe option is chosen for ease of use. The on and off times can then be specified.

5.2.5 Results

This tab contains a list of all the spatial results that can be recorded throughout thesimulation. One can pick to enable or disable one or more of the results to save memory asneeded.

5.2.6 Advanced options tab

WARNING: This tab includes options which should only be changed if you are quitefamiliar with the meshing algorithm and techniques used .

DEVICE:

DEVICE:

SOLVER TYPE can be set to gummel or newton. Please see this page to learn aboutthe function of each solver type. MULTITHREADING if enabled, the user can choose to divide up and run the simulation overmultiple threadsFERMI STATISTICS if enabled, fermi statistics will be used in the solvers. Please see thispage to learn more about the details of the fermi statistics model.

The following applies to both sections on Poisson Solver Controls and Drift-Diffusion SolverControls:

USE DEFAULTS: checked by default, will use an iteration limit of 40, absolute tolerance of1e-06 volts and a maximum update value of 5 volts.ITERATION LIMIT: Takes a value between 1 and 10000. This limits the number of iterationsof the Poisson or drift-diffusion solver that may be run.ABSOLUTE TOLERANCE: For a calculation to be considered converged, this determinesthe maximum absolute change between iterations that can exist. For the Poisson solver,the step converges when

kk VV 1

where δ is the tolerance and V is the electrostatic potential. For the drift-diffusion solver,both the electron and hole quasi-Fermi levels must converge:

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kFp

kFp

kFn

kFn

EE

EE

1

1

MAXIMUM UPDATE: To help the calculation converge, the maximum change that will beapplied to estimate the solution at the next step can be clamped. This value is in multiplesof the thermal voltage (kT/q).

Initialization:INITIALIZATION: disabled by default, but can be enabled if the start bias in a voltage sweepis far from the solver's initial guess. More steps will help bring the initial guess closer to thestart value but will cause the simulation to take longer.

5.2.7 Solver type

DEVICE simultaneously solves the equations for the electrostatic potential (Poisson’sequation) and charge (drift-diffusion equations). The solutions to these equations must beself-consistent, i.e. the charge calculated from the drift-diffusion equations satisfies thePoisson equation, and vice versa. Two common approaches are used to solve this systemof equations: Gummel’s method and Newton’s method.

Gummel’s method decouples the charge problem from the electrostatic potential problemat each step. As both of these equations are non-linear, they must in turn be solved usingan iterative or direct method. First, the electrostatic potential is solved holding the chargefixed. Next, this solution to the electrostatic potential is used as a fixed input to the chargeequations, and those are updated. This process continues until the solution is self-consistent. Gummel’s method is stable and efficient for devices where the currents aresmall and the variations in the charge distribution are not too extreme (meeting the criteriathat the charge and electrostatic potential are weakly coupled problems). Gummel’smethod should not be used for transient simulations or simulations involving high levels ofcharge injection.

Newton’s method is the classic approach to solving a system of non-linear equations. Inthis method, the electrostatic potential and charge are solved for simultaneously, and allare updated at each step. Newton’s method requires a good initial guess in order that it willconverge, and can be more difficult to converge than Gummel’s method. However, Newton’smethod can handle devices where the variations in charge density are large. Newton’smethod must be used for transient simulations.

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5.2.8 Fermi statistics

Electrons and holes are fermions, and therefore obey Fermi-Dirac statistics. At a finitetemperature, the energy distribution of the electrons is described by the Fermi-Diracfunction,

where k is the Boltzmann constant, T is the temperature, and Ef is the Fermi energy.When E-Ef>>kT, the Fermi-Dirac distribution can be approximated by the Boltzmanndistribution,

Often in semiconductor devices, when the net doping density is sufficiently low (non-degenerate), the Fermi energy is located within the band gap (carriers are forbidden fromhaving energies within the range of the band gap), far from the band edges. When thecondition E-Ef>>kT is satisfied (typically for |E-Ef|> 3kT), the Fermi-Dirac distribution canbe replaced with the Boltzmann distribution.

The carrier density is calculated from the integrated product of the Fermi-Dirac distribution(probability of occupancy) and the density of states (available states to occupy). Forelectrons, the equation is

When the Fermi-Dirac distribution is used, this integral does not have an analytic solution,and must be approximated numerically. However, for non-degenerate conditions, the Fermi-Dirac distribution is approximated by the Boltzmann distribution, and the precedingequation reduces to

describing the electron density at equilibrium (Nc is the effective density of states and is aconstant related to the specific properties of the semiconductor).

5.3 MonitorsThe following types of monitors are available in DEVICE:



Charge monitorsCharge monitor records electron and hole densities in the monitor space. It can alsointegrate the total charge within the monitor surface/volume.

Electric Field monitorsElectric field monitor records the electric field within the monitor region as well as theelectrostatic potential. Using this information, it can also calculate the total charge withinthe monitor surface/volume.

5.3.1 General tab

Charge monitorMONITOR TYPE: The monitor geometry can be chosen. It can be a point, a line in anydirection, a plane normal to any of the axis or a 3D monitor.RECORD ELECTRONS/HOLES: If this option is checked, the electron/hole densities willbe recorded. These will be in units of 1/cm 3 for both n and p.TRUNCATE MESH: Since the generated mesh is triangular and the monitors arerectangular, if this option is chosen, the mesh points will be interpolated onto the monitorboundaries.INTEGRATE TOTAL CHARGE: The total number of electrons/holes will be calculatedwithin the monitor surface/volume. This will be in unitless ( total number of chargedcarriers) in 3D and in units of 1/m ( number of carriers in a meter) in 2D for both n and p.

Electric field monitorMONITOR TYPE: The monitor geometry can be chosen. It can be a point, a line in anydirection, a plane normal to any of the axis or a 3D monitor.RECORD ELECTRIC FIELD: If this option is checked the electric field across the monitoris recorded.E will be in units of volts/m.RECORD ELECTROSTATIC POTENTIAL: If this option is checked, the electrostaticpotential across the monitor is recorded. V is in units of volts.CALCULATE NET CHARGE: If this option is checked, the net charge within the monitorsurface/volume is calculated using Gauss's law by integrating the electric field fluxthrough the box surface. The results are in units of Coulombs in 3D simulations andCoulombs/m in 2D simulations.

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5.3.2 Geometry tab

The geometry tab contains options to change the size and location of the monitors.

5.4 GenerationThe following types of Optical generation objects are available to be superimposed on thestructure in DEVICE:

Bulk GenerationThe bulk generation object allows the user to define a region of bulk optical generation. Theregion geometry as well as the parameters below can be specified:

ILLUMINATION FACE: The direction of illumination can be chosen by picking one of the sixsides of the cubic region.SPECTRUM: The spectrum of the illumination can be chosen. For example, solar (AM1.5G) will import the spectrum of the sun.MATERIAL: The semiconductor onto which the generation is superimposed can be chosenfrom this drop down menu.INTERFACE REFLECTION: Either an air interface or an anti reflective coating interface canbe chosen as the boundary of the generation region. In the case of the ideal anti reflectivecoating, all light will be assumed to penetrate into the semiconductor, whereas in the airinterface case, reflections from the air-semiconductor interface could take place.

A plot of the generation rate versus position will be generated on the bottom right corner ofthe edit window.

Import GenerationThe Import generation object allows the import of a user defined optical generation region.The location of the object is specified via the edit window. IMPORT NEW DATA: opens file browser to select data file. The file must be in Matlabformat (.mat) and contain fields "x", "y", "z", and "G", where "x", "y", and "z" are 1D arraysspecifying the rectilinear grid, and "G" is a 3D array (with dimensions NX x NY x NZcorresponding to the rectilinear grid) whose entries are the optical generation rate in units of

m-3s-1.

5.5 DopingThe following types of Doping objects are available to be superimposed on the structure inDEVICE:



Constant Doping RegionThe constant doping object allows the user to define a region with constant doping. Theregion geometry as well as parameters can be entered.DOPANT TYPE: The dopant type can be n-type (donors) or p-type (acceptors).CONCENTRATION: The concentration of the dopant can be entered.

Diffusion RegionThe diffusion region object allows the user to define a region with a dopant concentrationprofile. The region geometry as well as parameters can be entered.DOPANT TYPE: The dopant type can be n-type (donors) or p-type (acceptors).SURFACE CONCENTRATION: The concentration of the dopant at the surface (the peakconcentration) can be entered.FACE: The side of the region where the surface concentration is defined (i.e. where thediffusion source originates). For example, "upper y" refers to the face defined by "y max".JUNCTION WIDTH: The width of the doping profile from surface (peak) concentration toreference concentration at the edge of the diffusion region.DIFFUSION FUNCTION: The doping concentration profile, can be gaussian or thecomplementary error function (erfc).REFERENCE CONCENTRATION: The doping concentration on the exterior of the box(excluding the originating face).

Import Doping RegionThe Import doping object allows the import of a user defined spatial doping profile. Thelocation of the object is specified via the edit window. IMPORT NEW DATA: opens file browser to select data file. The file must be in Matlabformat (.mat) and contain fields "x", "y", "z", and "N", where "x", "y", and "z" are 1D arraysspecifying the rectilinear grid, and "N" is a 3D array (with dimensions NX x NY x NZcorresponding to the rectilinear grid) whose entries are the doping concentrations in units of

cm-3.DOPANT TYPE: The dopant type can be n-type (donors) or p-type (acceptors).

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5.6 ContactsThe Contacts table allows the user to define electrical contacts in the simulation region andassign a bias to them.

The add/delete/edit buttons can be used to add a new contact, delete a contact or edit theproperties of a contact respectively. The name of the contact can be typed in the Name column, the geometry of the contactcan be picked from a drop down menu from the choices available according to thesimulation objects. The contact can be set to Ohmic, Schottky or None.

SOLVER MODE: The mode of the solver is consistent with the mode picked in thesimulation region and can be set to dc to transient.

DC MODE:

In the DC mode, the bias assigned to each contact can either be fixed at a value or sweptover a range of DC values. In the sweep case, the start and stop biases as well as intervaland the number of points in the sweep can be specified. Alternatively, the user canmanually enter a range of values for the voltage to sweep over. Series and shunt resistorscan also be added to the voltage source to model more complicated circuits.



TRANSIENT MODE:

In the transient mode, the bias assigned to each contact can either be fixed at a value( this is the same as the fixed bias in DC mode) or transient, swept over a range of timedependant values. In the transient case, the values for each voltage point as well as thetime point can be entered in a table. Series and shunt resistors and capacitors can also beadded to the voltage source to model more complicated circuits. The resistance andcapacitance for these elements can also be specified as a function of time. If only one pointis specified in the table, then a constant value is assumed for that element. The values forthe voltage Rs and Cs will be linearly interpolated in time for consistency.

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5.7 Equation interpreterThe fields for numeric parameters can be used as a simple calculator. For instance, if youwish to set a value to the square root of 3 divided by e, just enter sqrt(3)/exp(1) into thefield. The expression will be automatically evaluated when you press Enter or click on adifferent field. Equations which become undefined (i.e. 1/0) should be avoided.

The following table provides a list of available operators and constants.

Category Syntax

Algebraic operators +, -, *, /

Trigonometric operators sin, cos, tan, asin, acos, atan, atan2,sinh, cosh, tanh

Power operators or **, exp, log10, log, sqrt

Logical operators >, <, >=, <=, ==, !=

Other operators abs, mod

Constants c - Speed of light in m/spi - The value of Pi

Examples2 10sqrt(3)/exp(1)sin(45*pi/180)

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6 Running simulations and analysis

This section describes the general operations of running a simulation and performing ananalysis. Information on how to set up optimization and parameter sweep projects is alsodescribed here. The contents are organization into the following chapters. For moreinformation on datasets, see Introduction to datasets in the Scripting chapter.

Resource ManagerRunning a simulationAnalysis toolsVisualizerResults ViewOptimization and parameter sweeps

6.1 Resource ManagerBefore running any simulations, the computing resources must be configured. This is donethrough the resource manager. It can be easily accessed by pressing the resources button

in the main toolbar. These settings are saved on a per user basis. For moreinformation, see the Parallel computing video.

In DEVICE, the "Processes" field is disabled since distributed simulations are notpermitted.

Resource Configuration

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USERS WITH A SINGLE LICENSEResourcesThis section allows the number of processes for localhost to be changed as well as thename. For advanced configuration options, see Resources Advanced Options .

Configuration testRun tests to make sure MPI username and password are set correctly. It also performsother checks such as engine path verification. If the tests pass, then we can be sure thatthe current simulation will run.

USERS WITH EXTRA ENGINE LICENSESResourcesIf you have extra engine licenses and Lumerical software installed on other computers onthe network, they can be added as additional computation resources to perform multiplesimulations in parallel. This is especially useful for parameter sweeps and optimizationprojects where many iterations need to be performed. The resources can easily be turnedon and off depending on whether they are free to compute at the time.

Requirements of each additional resource:Must be the same operating system as localhostMust be the same system type as localhost (cannot mix 32-bit with 64-bit)Must have the same version of Lumerical software as localhostMust have the same version of MPI as localhostMust have a user account with the same login and password as localhostMust have access to the simulation files via a network drive

To add a new resource:1. Click the add button.2. Set 'active' if you plan to use the resource right away or 'inactive' if you plan to enable it

later3. Set a name for that resource4. Specify the IP address of the hostname that the computer uses on the network5. Set the number of cores that you would like it to use6. Set any advanced options.

If many resources have advanced options that need to be changed, the 'Duplicate' buttonwill be useful.

Configuration testThis section of the window is used to test the communication to the additional resources. It runs a series of tests and will report any warnings or errors that may prevent a distributedsimulation from running such as mismatched software versions, user credentials orcommunication problems.

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6.1.1 Resources Advanced Options

Advanced OptionsEach resource canhave customizedsettings if required.

Resource advanced options

MPICH OPTIONSJOB LAUNCHING: Whether or not to tell mpiexec to spawn processes in local session orvia remote job launcher. The default setting is "Bypass mpich daemon on localhost", whichwill add the –localonly command line option and skip the –host command line options (onlyif the host name is localhost). The setting "Standard", adds the argument -host <IP/Hostname>. The last setting "Bypass mpich on localhost" will exclude mpich entirely. USE PROCESSOR BINDING: Tells mpiexec to specify which CPU each process will runon, when mpiexec supports it. On Windows, it adds the –binding option with the valuecomputed through the lumnuma class. This option is not supported on Linux and Mac. Customers interested in this functionality on Linux and Mac should consider using numactl.EXTRA MPIEXEC OPTIONS: Allows the user to specify advanced options to mpiexec. Ifset, the specified mpiexec path is used instead of the default mpiexec co-packaged withthe software.SUPPRESS ANY DEFAULT MPIEXEC OPTIONS: removes the default arguments in thempiexec commandSET MPIEXEC ENGINE PATH: Allows the user to specify the path to their mpi executable.

PRODUCT OPTIONSCREATE LOG FOR ALL PROCESSES: Each parallel process will create a log file. Adds

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the –logall command line option.EXTRA COMMAND LINE OPTIONS: Allows the user to specify advanced options toengine. Appends the text immediately after the engine command.SET ENGINE PATH: Allows the user to specify path to product engine. If set, the specifiedpath is used instead of the default path which is relative to the executable binary.

The bottom window displays the final command which will be used to run the simulation.

6.2 Running a simulation

When the simulation setup is complete and the resource setup passes the configuration

tests, it is time to run the simulation. Clicking on the RUN button in the toolbar willlaunch the job monitor window with the simulation already running. If you have not alreadysaved your simulation, you will be prompted to do so. The simulation project file must besaved in order to run after which the data can then be analyzed.

The job monitor window allows you to see the status of your jobs, as well as allowing youto pause or quit the jobs. Errors that occur during the simulations are displayed here.

Job Manager

The elements of the job monitor window are as follows:ENGINE: Shows which computational resource is being used. The name is specified bythe user.STATUS: Shows the state of the job. e.g. running, paused, finishedPROJECT FILE: Shows the location of the file that is being simulated.

MESHING STATUS: Indicates the status of the meshing process; If the mesh hasalready been calculated, the status will be "Loaded". If not, the status will calculate themesh starting with "Applying global constraints", then "Refining mesh by doping", andthen "Finished". BIAS POINT: Shows the bias point step as the simulation loops through all the specifiedcontact bias values. For example 2/25 implies that the simulation is currently running forthe second bias point out of 25 specified points.PROGRESS: Shows the percentage of the time taken so far as compared to the



maximum time remaining.QUIT & SAVE: Stops the simulations and saves the data obtained up to that point. Theprogram will be in Analysis mode.QUIT & DON'T SAVE: Stops the simulations and does not save any data. The programwill be in Layout mode.FORCE QUIT: Closes the job monitor window and forcefully terminates all simulations.This option should ONLY be used when the other Quit options don't work properly. When simulations are stopped with Force Quit, they may not check-in their license,which means you may have to wait several minutes before another simulation can be run. No simulation data will be saved.TOTAL PROGRESS BAR: The progress bar indicates how much of ALL the simulationsare complete, with the length of the progress bar is determined by the sum of the“maximum simulation times”.

To access actions for each job, right-clicking anywhere on the row will bring up a contextmenu with the following options:

PAUSE: the engine is signaled to go into a wait mode (it will stay running, but notconsume CPU)CONTINUE: restarts a paused jobQUIT AND SAVE: The engine will stop the current simulation job and attempt to save thedata created so far. QUIT AND DON'T SAVE: The engine will stop the current simulation job and does notsave any data.FORCE QUIT: Forcefully terminates the current simulation job and does not save anydata. This options should ONLY be used when other Quit options don't work properly.When simulations are stopped with Force Quit, they may not check-in their license,which means you may have to wait several minutes before another simulation can berun. VIEW JOB DETAILS: Opens up a modal dialog that contains the standard outputmessages from the engine processes.

Note: More informationFor more information about running Lumerical simulations, including running on clusters,using a job scheduler, preparing batch files, and using extra engine licenses, see theOnline Help section User Guide - Running Simulations.

6.3 Analysis toolsThis section describes the way in which the integrated analysis routines are used tovisualize and analyze simulation data. The manner in which the analysis routine interactswith the overall simulation environment is described in the next section: Analysis tools and the simulation environment . This is followed by sections tofamiliarize the user with the operation of the analysis routines.

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In the first section, the two general ways in which data can be visualized and analyzed isdetailed. The plotting functions, a central component to the overall analysis routines, aredescribed in Figure windows section. The section entitled Data export describesdata can be exported to plot in other software packages for further analysis or formalpresentation. More advanced analysis can be performed with the extensive scriptinglanguage, as described in the Scripting language section. Finally, visualization of theresults and data using the Visualizer feature is explained.

6.3.1 Analysis tools and the simulation environment

Before describing how the analysis routines are used for data visualization, it is importantto understand the way in which the integrated analysis tool interacts with the simulationenvironment. Following the completion of a simulation, the simulation data is written intothe simulation project file; even premature termination of a simulation results in a partialdataset being written to the file. When the simulation completes and the EXIT button ispressed, or the simulation is prematurely terminated by pressing the EXIT button, theproject file will be in Analysis mode, meaning that any modification of the data will requireswitching back to the layout mode.

In Analysis mode, simulation object properties can be viewed, but not edited. This ensuresthat at any given time, the simulation data results corresponds to the configuration of thesimulation project. Once in the analysis tool, the user continues to analyze the simulationdata until they either wish to close the application, or they decide they would like to alterthe simulation objects and re-perform the simulation. By exiting the analysis routines andreturning to the layout editor, existing simulation data will be erased.

6.3.2 Figure windows for plots and images

Simulation results can be visualized using 1D line, 2D surface and 3D vector field plots. These plots can be created from within the results visualizer, or from the scriptinglanguage.

The figure window controls are slightly different for each type of plot. For example, only the3D vector plot provides controls for 3D rotation of the view. All plots support operation suchas axis labels, zoom, export to JPG, etc.

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6.3.3 Data export

In some cases, the user may wish to export the simulation data to take advantage of theadvanced plotting and data analysis tools not available in Lumerical's products. Data exportcan be done in a number of ways, but in general the use of the scripting language will berequired. The write script command can be used export data to a text file, or thematlabsave command can be used to save data to .mat files. Results stored in

datasets can also be export to Paraview (for sophisticated data visualization) with the vtksave command.

6.3.4 Visualizer

The Visualizer is a tool for analyzing data. Simulation data from a variety of objects(monitors, parameter sweeps... etc) can be sent to a Visualizer.

Data that gets added to the Visualizer is retained until it is removed (ie. with the "Remove"button or by pressing "X" on the top right corner of the window). This is useful forcomparing results across different data sets. The upper-left portion of the window is theplot area, which displays the current data defined by the settings in the upper-right of thewindow (plot settings). The following sections describe the many options available forcontrolling what data will be displayed in the plot area. These sections can be minimized ifmore area for plotting is required.Visualizer controlsVisualizer attributesVisualizer parameters

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Visualizer

The surface plot option is also used to plot a number of 3D results. The plot will contain a3D outline of the structure and the results are shown on a planar cross section of thatoutline. To change the plane position and/or orientation, move the arrow perpendicular tothe plane, grabbing it with a mouse left click much like a drag action.



See the Visualizer video in the online User Guide for additional information on the visualizer.

6.3.4.1 Visualizer controls

The settings control the overall typeof plot and the labels applied to it.

Plot type: select Line, Surface orVector plotManual plot: Disable auto-refresh.Useful when visualizing largedatasets.Export to: export figure to JPEG,text file or clipboardView options: show/hide Attribute &Parameter panes

Line plot: Choose this option to plota 1D vector versus another 1Dvector. For matrices with more than1 dimension, a slice of the matrixwill be automatically chosen. Youcan use the parameters table on thebottom to choose which dimensionto slice and which to plot on the x ory axis.

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Surface plot: Choose this option tocreate a 2D image plot of monitordata. For matrices with more than 2dimensions, slices of the matrix willautomatically be chosen. you canuse the parameters table on thebottom to choose which dimensionsto slice and which to plot on the x ory axis.

Vector plot: Choose this option tocreate a 2D/3D vector plot of monitordata. Choose the parameters tableto slice a frequency point. It ispossible to create a vector plot ofquantities such as the electric field,magnetic field, poynting vector, etc.

TIP: It is often more meaningful toplot the poynting vector rather thanthe fields. Plots of the electric fieldwill often contain vectors pointing indifferent directions representing theoscillation in the field direction. Themore interesting quantity to plot isthe poynting vector where thedirection of power flow can bevisualized.

TIP: It can be helpful to create anelectric field vector plot to studycircularly polarized or ellipticallypolarized beams. See the exampleon our knowledgebase.

The plot settings can be further edited by click on the pencil icon on the top left corner of

the plot window .



For line plots, the followingare available:

TITLE: The title of the plot canbe specifiedX/Y LABEL: The x and ylabels for the plot can bespecifiedSET AXIS LIMITS: The x andy limits for the axis can besetEDIT LEGENDS: The legendsfor the plots can be specifiedNUMBER OF TICKS: Thenumber of axis dividers on thex and y axis can be specified.The default is 10.

One can also choose toshow/hide the title andlegends, draw the x and yaxis at (0,0), plot multiplefigures using the same color,plot the x and/or y axis on alog scale, show/hide grids forthe axis and choose to showthe plots in grey scale.

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For surface plots, thefollowing are available in 2Dsimulations:

PLOT TYPE: Can be a 2Dimage plot or a 3D surfaceplot. In the 2D image plot, thevalues are indicated using thecolor bar. In the surface plot,the values are also plotted inthe third dimension.

SHOW: Can be "surface"which will contain the valuesat each mesh point only, or"surface and mesh" which willsuperimpose in black, themesh grids on top of theplots, or "mesh only" whichwill only plot the mesh grid incolor.

AXIS SCALE OPTIONS: Canbe "square" which will makesure the two axis are plottedto the same size, or "equal"which will use the same scalefor both such that the plot willbe to scale.

LOG SCALE: Will plot theresult on a log scale.LABELS: the x/y/z labels canbe specified.COLOR BAR: The color barlimits can be specified.



For surface plots, thefollowing are available in 3Dsimulations:

SHOW: Can be "surface"which will contain the valuesat each mesh point only, or"surface and mesh" which willsuperimpose in black, themesh grids on top of theplots, or "mesh only" whichwill only plot the mesh grid incolor.

AXIS SCALE OPTIONS: Canbe "square" which will makesure the two axis are plottedto the same size, or "equal"which will use the same scalefor both such that the plot willbe to scale.

LOG SCALE: Will plot theresult on a log scale.LABELS: the x/y/z labels canbe specified.COLOR BAR: The color barlimits can be specified.

CLIP PLANE: The clip planecan be shown on top of a 3Dsurface plot. This plane can

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be defined by defining 2 (x,y,z) vectors one of which is thenormal to the plane. Forconvenience, there are alsothe quick options of choose ax normal/y normal /z normalplane. This plane will be ableto cut through the the 3Dstructure and give insight intothe inside of the 3D plot. Theinside out option will flipwhich side of the plane isshown.



6.3.4.2 Visualizer attributes

An attribute is a quantity to plot (ie. Power transmission vs frequency). Multiple attributescan be sent to a single visualizer. When using line plots, each attribute will appear as aseparate line. When using image and vector plots, the selected attribute will be shown.

DATA SET: full data set name (can contain multiple attributes)ATTRIBUTE: attribute nameVECTOR OPERATION: selects a particular component of a vector attribute e.g. (Ex, Ey, |E| 2)SCALAR OPERATION: selects a particular component of a scalar attribute e.g. (real,imag, abs, angle)

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SCALE: multiplier for the data being plottedLEGEND: this name will be shown in the legend of the plotNOTES: additional information added by the user about the attributeVIEW DATA: allows users to view the data in a table format as shown below

In this table format, users can select any portion of the data and "Copy" or "Export" it into atext file. Alternatively, users can also send any portion of the data into the ScriptWorkspace .

6.3.4.3 Visualizer parameters

In addition to the attributes, data sets also contain the associated position vectors (eg:position, frequency).

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ATTRIBUTES: Name of the associated attributePARAMETERS: Name of the parameterACTION: Control how the parameter is treated in the plot. For example, select which axisto plot the parameter on.VALUE: displays the value if it is a singular value or is blank if there is a vector of values

Plotting multi-dimensional attributesLine plotsOne parameter must be selected to plot on the X axis. All other non-singleton parametersmust be set to Slice. A specific slice can then be selected for those parameters.

Surface plotsTwo parameters must be selected to plot on the X and Y axis. All other non-singletonparameters must be set to Slice. A specific slice can then be selected for thoseparameters.

Vector plotsThe spatial dimensions (x,y,z) are always selected to plot on the X, Y, Z axes. All non-spatial parameters must be set to Slice. A specific slice can then be selected for thoseparameters.

6.3.5 Results Manager

The Results Manager is a tool for analyzing simulation data. The Results View windowshows all the results for the simulation object that is currently selected in the Object Tree.The Script Workspace and Script Favorites windows work in conjunction with thescripting environment to provide additional GUI-based functionalities.

When used in conjunction with the Visualizer , the Results Manager provides a veryuseful and intuitive way of analyzing and visualizing variables and results through the GUI.

6.3.5.1 Results View

The Results View window shows all the results for the simulation object that is currentlyselected in the Object Tree. Any simulation object that have results will be displayed witha symbol on the bottom-right corner. The name of the available results, and thecorresponding dimensions or are displayed. One can right click on any of the results todisplay them in the Visualizer , or to send the to the Script Workspace for furtherpost-processing.

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With the use of datasets, allowing one to package raw data into meaningful results that canbe easily parameterized and visualized. The results for all the standard monitors can beretrieved in the original raw, un-parameterized matrix form (using getdata), or in datasetform (using getresult). For example, in the Results View figure above, the results listedunder “rawdata” can be obtained using the “getdata” command. The results listed under"results" are datasets, and can be obtained using the “getresult” command (thesecalculations will only be carried out when they are visualized). The icons associated witheach result reflect the type of result:

Matrix: this is a simple matrix result, with no associated parameters

Matrix dataset: this is a parameterized matrix results that contains at least anattribute (result), and a associated parameter

Rectilinear dataset: this is a parameterized matrix result that is associated with arectilinear grid

Unstructured data: This is a set of data that is not structured in form of a dataset ora matrix and rather consists of several different types of results

String

For more detail on how to work with datasets in the scripting environment, please see Accessing simulation data in the User Guide. Analysis group objects from the Objectlibrary have been updated to return datasets. For an example of how to define dataset



results in an analysis group, please see Using analysis groups.

The raw data results are all un-parameterized, simple matrix results. To createparameterized matrix datasets from matrices, use the "Send to script" option to copy thevariable into the Script Workspace, and follow the instructions here .

6.3.5.2 Script Workspace and Script Favorites

The Script Workspace shows all the variables in the current scripting environment. Thevariables' current values as well as the corresponding dimensions are shown in a listformat. Users can use the Visualizer to visualize any variable listed in the ScriptWorkspace by right-clicking on the variable and selecting "Visualize".

The icons in the script workspace above shows that while "sigmaabs" and "sigmascat" areparameterized matrix datasets (since they were the results returned directly by the crosssection analysis groups), "sigmaext" is a result that we defined in the script, and istherefore a simple un-parameterized matrix. For example, simply right-clicking onsigmaext and selecting "Visualize" will generate the following plot in the Visualizer:

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Here, the extinction cross section is plotted as a function of the index value. To associate itwith the corresponding frequency array, select the "Create visualization" option, which willopen the "Visualization Creator" dialog window:

This window allows users to set the name of the parameterized variable (sigmaext_vs_f)and its parameters (f). Once this is defined, the visualization creator will generate thecommands necessary for creating the parameterized dataset in the Script Favoriteswindow. When this command is ran, it will send the new parameterized variable to theVisualizer, which will plot the variable as a function of the user specified parameter.

Generated Command Generated Figure



In addition to the commands generated by the visualization creator, the Script Favoriteswindow also allows users to define their own favorite commands by selecting "Newcommand" and "Edit".

6.4 Optimization and parameter sweepsThis section describes the way in which the optimization and parameter sweeping projectsare set up. This feature allows users to automate the process of finding desirableparameter values by running a large number of simulations. For additional information, seethe Optimization and sweeps video. An example Optimization and Sweeps tab is shown in the screenshot below:

At the top of the window is a toolbar containing the following buttons:

Creates a parameter sweeping task.

http://www.lumerical.com/support/courses/fdtd_optimizations_and_parameter_sweeps/video.html

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Creates an optimization task.

Creates a yield analysis task.

Opens an edit window for the selected project where one can modify its properties.

Deletes the selected project.

Runs the selected sweep or optimization with the resources currently set in theresource manager.

The Animate function allows you to view the structures that will be simulated in a parametersweep or optimization in the CAD before you run the project:



6.4.1 Optimization

An example Edit Optimization window is shown in the screen shot below:

The optimization project allows users to use built-in algorithms as well as define their ownoptimization algorithms. For examples on how to set up and run an optimization project,please see Optimize a design. As can be seen from the screenshot above, there is a SETUP tab as well as anADVANCED tab.

Setup Tab

There are three sections in the setup tab:

OPTIMIZATION CONFIGURATION:This section contains the choice of algorithm as well as all the input parameters that areneeded to set up an optimization project using a built-in algorithm:ALGORITHM: The optimization algorithm used for this project

PARTICLE SWARM: The built-in particle swarm algorithm (see Particle SwarmOptimization for more details on the algorithm).

USER DEFINED: The user-defined algorithm specified in the ADVANCED TAB.TYPE: Choice of maximizing or minimizing the figure of meritMAXIMUM GENERATIONS: The maximum number of generations for this optimizationproject.GENERATION SIZE: The generation size (number of child per generation) for this

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optimization project.RESET RANDOM GENERATOR: If this option is selected, the random number seed to thesame value before starting the optimization. Otherwise a new initial condition is chosenevery time this optimization project is run. TOLERANCE: The convergence criteria for the optimization to terminate. If set to 0, theoptimization will run until the maximum number of generations has been reached.

PARAMETERS:This section contains the optimization parameters and the range of values used for thisproject. One can ADD/REMOVE parameters via the buttons on the right. The parameterscan be chosen from the simulation model by double-clicking on the selected parameterfield. The types, min/max values and units of the selected parameters can also be set in asimilar fashion.

FIGURE OF MERIT:This section contains the figure(s) of merit (FOM) used for this project. One can ADD/REMOVE FOMs via the respective buttons. FOMs are typically defined as output variablesof monitors or analysis groups, which can be selected from the simulation model bydouble-clicking on the selected FOM field. Once the FOMs have been defined, one canselect the FOM to be used in this project by clicking SELECT TO OPTIMIZE (note that allother FOMs will be ignored in this optimization).

Advanced Tab

The ADVANCED tab is shown in the screen shot below:



This tab allows users to define their own optimization algorithm, and is only editable if theUSER DEFINED option is selected in the SETUP tab. The Advanced tab is divided intotwo sub-tabs:

USER DEFINED ALGORITHM:This tab contains the scripts which define the customized optimization algorithm (byspecifying the first and next generation scripts). The SCRIPT OUTPUT shows the output of a test which runs the user defined algorithm with ananalytical function. If there are no syntax errors in the script, you will see the line <scriptcomplete> in the script output, otherwise the location of the error will be given. This test isconducted every time the TEST button is pressed, and a window showing the OptimizationStatus is displayed. FIGURE OF MERIT SCRIPT:This tab contains the script which defines the custom FOM. To enable this window, selectthe USER FIGURE OF MERIT SCRIPT checkbox. The only variables that can be used inthis script are the ones that are defined in the FOM section of the SETUP tab. For anexample that uses a user-defined optimization algorithm, see User Guide.

6.4.2 Particle Swarm Optimization

Particle Swarm Optimization (PSO) is a population based stochastic optimizationtechnique, inspired by the social behavior of flocks of birds or schools of fish [1,2], and haswidely been used for various kinds of design optimization problems [2] includingnanophotonic design [3-7]. In PSO, the potential solutions, called particles, are initializedat random positions, and then move within the parameter search space. The particles aresubject to three forces as they move:1. Spring force towards the personal best position, p, ever achieved by that individual

particle2. Spring force towards the global best position, g, ever achieved by any particle.3. A frictional force, proportional to the velocity.

The algorithm then follows these steps1. Set the number of particles N and initialize the positions x 2. Evaluate figures of merit (FOM) and find p and g 3. Calculate the new velocities v for each particle based on the forces applied to the

particle

1112211111 1 ttttttt vxgcxpcvv (1)

4. Update the positions x of each particle based on the velocity

ttt vxx 1 (2)

5. Repeat from step 2 until convergence is achieved

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In Eq. (1), t is the iteration counter; c1 and c

2 are the cognitive and social factors,

respectively; ω is called the inertial weight; and η1 and η

2 are random number between 0

and 1. Lumerical's PSO implementation uses default values of c1, c

2 and ω that have

shown to converge well in many test optimization problems for photonic design problems. Adetailed description of the algorithm and the difference coefficients can be found in Refs. [1]or [2].J. Robinson and Y. Rahmat-Samii, "Particle swarm optimization in Electromagnetics,"IEEE Trans. Antennas and Propagat. 52, pp.397 - 407 (2004).1. K. E. Parsopoulo and M N. Vrahatis, Particle swarm optimization and intelligence :

advances and applications, Information Science Reference, 2010.2. J. Pond and M. Kawano, “Virtual prototyping and optimization of novel solar cell

designs”, Proc. SPIE 7750, 775028 (2010), DOI:10.1117/12.8731143. M. Kawano and J. Pond, "Design Optimization of Photonic Crystal Organic Solar Cells

using the FDTD method in Combination with Particle Swarm Optimization," 7thInternational Conference on Optics-photonics Design & Fabrication, Yokohama, Japan,19S1-14, 2010.

4. J. G. Mutitu, S. Shi, C. Chen, T. Creazzo, A. Barnett, C. Honsberg and D. W. Prather,"Thin film silicon solar cell design based on photonic crystal and diffractive gratingstructures", Opt. Express 16, 5238, 2008

5. M.Shokooh-Saremi and R. Magnusson, "Leaky-mode resonant reflectors with extremebandwidths," Opt. Lett. 35, 1121, 2010.

6. R. Magnusson, M. Shokooh-Saremi,and E. G. Johnson, “Guided-mode resonant waveplates,” Opt. Lett. 35, 2472, 2010.



6.4.3 Parameter Sweeps

An example Edit Parameter Sweep window is shown in the screen shot below:

For examples on how to set up and run a parameter sweep project, please see Run aparameter sweep.

There are two sections in the Edit Parameter Sweep window:

PARAMETERS:This section contains all the input parameters that are needed to set up a parameter sweepproject. There are two ways to specify the inputs to the parameter sweep. If RANGES isselected, the table above is shown. One can ADD/REMOVE parameters via the respectivebutton on the right. The parameters can be chosen from the simulation model by double-clicking on the selected parameter field, and the types, min/max values and units of theselected parameters can be set in a similar fashion. If VALUES is selected, the followingtable is shown:

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The behaviour is similar to the description for the RANGES option above, except here everyvalue of the parameter is shown explicitly and can be edited one-by-one. Pressing the SETIN MODEL button automatically sets the parameters in the simulation model to have thesame value as the selected one.

NOTE: If two or more parameters are specified, they must have the same dimensions. Each sweep step will update all parameters values one column at a time (ie. this is not thesame as nested parameter sweeps). For information on how to set up nested parametersweeps, please see Nested Sweeps .

RESULTS:This section contains all the outputs from the parameter sweep.

6.4.4 Nested Sweeps

It is alsopossibleto usenestedparametersweeping. To add,simplyright clickon thecurrentoptimization orsweepandselect"Insert

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parameter sweep".Examples can befound inthe UserGuide aswell as intheapplicationexamples.

6.4.5 Yield Analysis

An example Edit Yield Analysis window is shown in the screenshot below:

For a tutorial on how to set up and run a yield analysis task, see Run a Yield Analysis.

There are three sections in this edit window:

CONFIGURATION:

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This section allows users to set the number of trials to use.NUMBER OF TRIALS: The number of trials to run.

PROPERTIES:This section allows the user to set the analysis parameters and the distributions. You canADD/REMOVE parameters via the buttons on the right. The parameters can then bechosen from the simulation model by double-clicking on the selected Parameter field. TheEdit Distribution window can be opened by double-clicking on the selected Descriptionfield.

Edit Distribution window:DISTRIBUTION TYPE:The following distributionsare available: Uniform,Gaussian, Lognormal,Truncated Gaussian,Truncated Lognormal,Discrete (uniform distributionwhere variables can onlytake discrete valuesspecified by the STEP).MEAN: Mean value of thedistribution for Gaussian,Lognormal, TruncatedGaussian, and TruncatedLognormal distributions.STD DEVIATION: Standarddeviation of the distributionfor Gaussian, Lognormal,Truncated Gaussian, andTruncated Lognormaldistributions.MIN: Minimum value or cut-off value for Uniform,Truncated Gaussian,Truncated Lognormal, andDiscrete distributions.MAX: Minimum value or cut-off value for Uniform,Truncated Gaussian,Truncated Lognormal, andDiscrete distributions.STEP: The discrete step



size of allowed values for Discrete distribution.SEED: The seed value usedto generate parametervalues. The seed used caneither be an automaticallygenerated random seed, orthe user can specify a valuefor the seed so that thesame results can beachieved each time the yieldanalysis is run.

RESULTS:This section contains the outputs of the yield analysis. Similarly to the parameters, userscan ADD/REMOVE results via the buttons on the right. The results can then be chosenfrom the simulation model by double-clicking on the selected result field.

The user can specify whether they want the yield analysis estimate for the result to bebased on the user specified min and max values. If "yes" is selected in the Estimationfield, the trial will be considered a pass if the result falls into this range. If there is morethan one result with a yield estimate, the final yield percentage will be the percent of trialswhere all of the results fall within the specified ranges.

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7 Scripting Language

Lumerical provides a powerful scripting language to manipulate simulation objects, launchsimulations and analyze results. Script commands can be entered directly into the scriptprompt, be run from a saved script file (.lsf), or entered into structure and analysis objects.

This section of the Reference Guide contains the syntax for each script command.

In addition to this chapter, the Scripting section of the online User Guide provides anintroduction to the scripting language, including examples that show how to export data toother file formats and tips for plotting in MATLAB.

The script functions have been organized into the following sections. You can also viewthe alphabetical list of commands, or watch a recorded video.

Section

System

Manipulating variables

Operators

Functions

Loop and conditional statements

Plotting commands

Adding Objects

Manipulating objects

Running simulations

Measurement and optimization data

Material database functions

GDSII

User defined GUIs

Creating your own script commands

The online version of this chapter includes examples for many commands.

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7.1 SystemSystem commands for interacting with the OS file system, running script files, etc.

System commands

Command Description

newproject Creates a new layout environment.

newmode Creates a new MODE layout environment.

new Creates a new simulation project file.

save Saves an fsp file or lms file.

load Loads an fsp file or lms file.

delrm

Deletes a file.

ls dir

Lists the files in a directory.

cd Changes the working directory.

pwd Returns the current working directory.

cp Copy a file.

mv Move a file.

exit Exit the application.

system Run command prompts.

fileexists Check if a file exists.

currentfilename Get the current filename.

filebasename Get the file base name from a string.

filedirectory Get the file directory from a string.

fileextension Get the file extension from a string.

copytoclipboard Copy to system clipboard.

pastefromclipboard Paste from system clipboard.

hide Hides the GUI.

show Shows the GUI.

clearlogwindow Clears output log window.

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version Returns the current version of the application.

versionfile Returns the current version of the file loaded by theapplication.

List of script commands

Command Description

getcommands Returns a list of available script commands.

Starting and stopping scripts

Command Description

running a script Type the script name to run it.

getpath Get the current path.

addpath Add a directory to the path.

which Where in the path is a file.

pause Pauses program for a time.

break Will stop a script file from executing at that line.

ESCAPE key To interrupt a script file from running or a long blockof commands from executing

File input and output

Command Description

format Set the precision of the script interpreter.

STD OUT

write Writes strings to text files or to standard output.

LDF files

loaddata Load variables or d-card data from ldf file.

savedata Save variables to ldf file.

savedcard Saves d-card data to an ldf file.

Text files

readdata Read text files.

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write Writes strings to text files or to standard output.

fld (field) files

asapexport Export monitor data to fld file.

asapload Load data from fld file.

asapimport Import data from fld file to Import source.

VTK files

vtksave Save in .vtk format

Touchstone files

touchstoneload Loads passive network data from a file containingTouchstone file formatted s-parameters.

Lookup tables

lookupclose Closes a file previously created with a lookupopencommand.

lookupopen Opens a file to write a lookup table.

lookupread Finds the nearest extracted value from a filecontaining a lookup table of design and extractedparameters.

lookupwrite Writes to a lookup table a design and an extractedparameter pair.

SPICE Netlist

importnetlist Imports an optical SPICE netlist

Comma separated value (csv)

exportcsvresults Exports simulation results to comma separated valueformatted files.

Debugging

Command Description

debug Opens the debug utility window.

See Also exportfigure , load , save

MATLAB functions

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Command Description

matlabsave Save workspace data to a Matlab .mat file.

matlabsavelegacy Save workspace data to a legacy Matlab .mat fileformat.

matlab Execute a MATLAB command

matlabget Get a variable from the MATLAB workspace

matlabput Send a variable to the MATLAB workspace

matlabload Load from MATLAB .mat file into workspace.

7.1.1 newproject

Create a new simulation project file. This command is NOT available in INTERCONNECT,please use new instead.

Syntax Description

newproject; Creates a new layout environment.This function does not return any data.

newproject(option); The options are 1: use default file and material database as template 2: use current file and material database as template 3: open a file browser to select and existing file as atemplate

The default option is 1.

See Also System level , new

7.1.2 newmode

Creates a new MODE layout environment.

Function has been deprecated. Use newproject instead.

Syntax Description

newmode; Creates a new layout environment.This function does not return any data.

newmode(option); The options are 1: use default lms file and material database as

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template 2: use current lms file and material database astemplate 3: open a file browser to select and existing lms file as atemplate


See AlsoSystem level

7.1.3 save

Saves an simulation project file. If the simulation has been run, the file will also contain thesimulation results.

Syntax Description

save; Open a file browser to save the file.This function does not return any data.

save(filename); Save with the specified name

See Also System level , load , loaddata , savedata , savedcard

7.1.4 load

Loads an simulation project file. If the simulation has been run, the file will also contain thesimulation results.

Syntax Description

load(filename); Loads the simulation file.This function does not return any data.

See Also System level , loaddata , save , savedata , savedcard , fileexists , dir

7.1.5 del

Delete a file.

Syntax Description

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del("filename"); rm("filename");

Deletes the file "filename".This function does not return any data.

See AlsoSystem level , delete

7.1.6 rm

Delete a file.

Syntax Description

del("filename"); rm("filename");

Deletes the file "filename".This function does not return any data.

See AlsoSystem level , delete

7.1.7 dir

List files in a directory.

Syntax Description

out = dir; out = ls;

The output is a string.Use ?dir; to write the value to the screen.

out = dir("directory"); out = ls("directory");

Lists the files in the specified directory.

See AlsoSystem level , load , splitstring

7.1.8 ls

List files in a directory.

Syntax Description

out = dir; out = ls;

The output is a string.Use ?dir; to write the value to the screen.

out = dir("directory"); out = ls("directory");

Lists the files in the specified directory.

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See AlsoSystem level , load , splitstring

7.1.9 cd

Change directory.

Syntax Description

cd; Opens a window to browse to a directory.This function does not return any data.

cd("directory"); Changes the working directory to "directory". Wheneveryou open an fsp file or run a script file, it will set theworking directory to the directory of the file opened.


7.1.10 pwd

Returns the current working directory.

Syntax Description

out = pwd; Returns the current working directory as a string.

See AlsoSystem level , currentfilename

7.1.11 cp

Copy a file.

Syntax Description

cp("file1","file2"); Makes a copy of file1 called file2. This function does not return any data.

cp("path1\file1","path2\file2");

Copies file1 in path1 to file2 in path2.

See AlsoSystem level , mv , pwd , copy (objects)

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7.1.12 mv

Move a file.

Syntax Description

mv("file1","file2"); Moves file1 to file2. This function does not return any data.

cp("path1\file1","path2\file2");

Moves file1 in path1 to file2 in path2.

See AlsoSystem level , cp , pwd

7.1.13 exit

Exit the application.

Syntax Description

exit; Exits the application. Same as exit(1);This function does not return any data.

exit(option); Exits the application. The option can be 1: Prompt user if a file needs saving before exiting. 2: Force the application to exit without prompting theuser.



7.1.14 system

The system command allows you to have the operating system (OS) execute a command,rather than the Lumerical script interpreter.

The system command does not return any data.

Syntax Description

system("command"); Run "command" at the OS command prompt.

See Also

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System level , readdata , exit

7.1.15 fileexists

Check if a file exists. The file extension must be specified. By default, the entire path willbe searched.

Syntax Description

out = fileexists("filename"); Returns 1 if the file existsReturns 0 if the file does not exist.

out = fileexists("c:\temp\file.txt");

Search for a file not in the path

See AlsoSystem level , getpath , which , pwd , load , loaddata , write , readdata

, currentfilename , rm ,

7.1.16 currentfilename

Get the current filename and directory.

Syntax Description

out = currentfilename; Returns the current filename as a string. If the current filename is not defined, this function returnsan empty string "".

See AlsoSystem level , fileexists , getpath , which , pwd , fileextension ,filebasename , filedirectory

7.1.17 filebasename

Get the file basename from a string.

Syntax Description

out = filebasename( "location/filename.ext" );

Returns the file basename as a string.

See AlsoSystem level , currentfilename , getpath , which , pwd

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7.1.18 fileextension

Get the file extension from a string.

Syntax Description

out = fileextension( "name.ext");

Returns the file extension as a string.


7.1.19 filedirectory

Get the file directory from a string.

Syntax Description

out = filedirectory( "location/filename.ext" );

Returns the file directory as a string.


7.1.20 getcommands

Returns the list of available script commands in the current script workspace.

Syntax Description

?getcommands; Returns a list of available script commands


7.1.21 Run script

Run a script by typing its name. The file must be in the current path. The path alwayssearches the current directory first. A script file is not passed variables, and does notreturn variables. All scripts have access to all of the variables defined in the currentworkspace.

It's best to avoid using the names of Lumerical script functions (i.e. plot) for the names ofyour script files. If a script file has the same name as a function, the script will be run (notthe function). This allows you to effectively re-define the behavior of a function, but it can

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cause confusion when done unintentionally.

Syntax Description

filename; Run the script file filename.lsf, if it exists in the currentpath.A script does not have a return type.

See AlsoSystem level , getpath , addpath , which , feval

7.1.22 getpath

Get the current path. By default, the current working directory and the script sub-directoryof the installation (eg. C:\Program Files\Lumerical\FDTD\scripts) are in the path.

Syntax Description

out = getpath; Returns the current path as a string. Use ?getpath; to print it to the screen.

See AlsoSystem level , addpath , which , pwd

7.1.23 addpath

Add a directory to the path.

Syntax Description

addpath("directory"); Adds a directory to the path. This function does not return any data.

See AlsoSystem level , getpath , which , pwd

7.1.24 which

Returns the full file pathname for the specified file.

This function can be helpful when you have added several directories to the Lumerical pathvariable and you want to check which files are being accessed.

Syntax Description

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out = which("filename"); Returns the pathname of the file "filename" as a string. Use ?which("filename"); to display the result to thescreen.

See AlsoSystem level , getpath , addpath , pwd , currentfilename , fileexists

7.1.25 pause

Pause program for a time.

Hit the space bar to force the script to continue. Hit the ESCAPE key to break the scriptat this point.

Syntax Description

pause(time); Pauses script for time, measured in seconds.This function does not return any data.

See AlsoSystem level , break , ESCAPE key

7.1.26 break

Stops a script from executing.

Syntax Description

break; Will stop a script file from executing at that line. A warningwill be generated.This function does not return any data.

See AlsoSystem level , ESCAPE key , pause

7.1.27 Excape key

Interrupts a script or long block of commands.

Syntax Description

ESCAPE key To interrupt a script file from running or a long block ofcommands from executing. A warning will be generated. Sometimes you may need to press escape several times,

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or hold it down to interrupt the script.

See AlsoSystem level , break , pause

7.1.28 format

The two format commands toggle the script interpreter between 2 output precision states.The commands print (?) and num2str() use this state to determine how many digits ofprecision to output.

Syntax Description

format long; Set script interpreter to 16 digits of precision.

format short; Set script interpreter to 6 digits of precision.

See AlsoSystem level , num2str , ?

7.1.29 loaddata

Loads workspace variables or d-card data from a Lumerical data file (ldf) file. If any currentvariables exist with the same names as those in the file, the current values will beoverwritten.

Syntax Description

loaddata("filename"); Reads data script variables or d-card data from thespecified file. This function does not return any data.

See AlsoSystem level , savedata , savedcard , workspace , load , fileexists

7.1.30 savedata

Saves workspace variables to a Lumerical data file (ldf) file. To save monitor (D-card) datato an ldf file, see the savedcard function.

Syntax Description

savedata("filename"); Saves all current variables to the specified file. This function does not return any data.

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savedata("filename", var1,var2,...);

Saves only variables with the specified names to file.

See AlsoSystem level , savedcard , loaddata , workspace , matlabsave

7.1.31 savedcard

Saves d-card data to a Lumerical data file (ldf) file. D-cards are generally used to storemonitor data.

Data is saved in the no norm state. See the units and normalization section of thereference guide for more information.

Syntax Description

savedcard("filename"); Saves all current d-cards (local and global) to the specifiedldf file.This function does not return any data.

savedcard("filename","name1", "name2",...);

Saves only the d-cards with the specified names, "name1","name2", etc.

See AlsoSystem level , savedata , loaddata , matlabsave

7.1.32 readdata

You can import numerical values stored in text files with the readdata command. Thiscommand will read a file with data in a row/column format. The data must be correctlyformatted so each row has the same number of columns. Readdata will ignore any linethat begins with a letter.

Syntax Description

M=readdata("filename.txt"); Will load the text file filename into matrix variable M. Anylines starting with a letter are ignored.

See AlsoSystem level , rm , write , str2num , findstring , replace , replacestring ,substring , fileexists

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7.1.33 write

Writes string variables to text files or to standard output.

Typically the write command is used to output data to a text file. If the specified file doesnot exist, it will be created. If it does exist, then the output string will be appended to theend of the file. The write command will automatically add a new line character at the end ofthe string.

On Linux systems only, the write command will output to the standard output (stdout) if afilename is not specified.

Syntax Description

write(my_string); Write my_string to the standard output (linux only).

write("testfile.txt",my_string);

Will write the contents of the string variable my_string totestfile.txt.This function does not return any data.

See AlsoSystem level , readdata , rm , num2str , ? , endl , format , fileexists

7.1.34 asapexport

Exports the desired monitor to a file for interfacing with BRO's ASAP. These files are calledfld files. The monitor must be a frequency power or a frequency profile monitor.

This command is available in FDTD and MODE.

Syntax Description

asapexport( "monitorname"); Export data from monitorname. By default, the firstfrequency point is exported. This function does not return any data.

asapexport( "monitorname",f);

Exports the frequency point specified by the index f.

asapexport( "monitorname",f, "filename");

Exports to the specified "filename" without opening a filebrowser window.

See AlsoSystem level , asapload , asapimport , addimportedsource

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7.1.35 asapload

Load data from an fld file from BRO's ASAP. asapload creates a d-card structure called"fld_data" which contains all the data in the file. If "fld_data" exists, it will be called"fld_data_2". After loading an asapfile with asapload, you can extract any desired data.,which can be

Ex, Ey, Ez, Hx, Hy, Hz, x, y, z power, frequency, wavelength, index


Syntax Description

asapload; Select the file to load with the file browser.This function does not return any data.

asapload( "filename"); Loads data from an fld file called "filename" without a filebrowser.

See AlsoSystem level , asapexport , asapimport , addimportedsource , fileexists

7.1.36 asapimport

Import an ASAP fld file into an ASAP source. This is equivalent to editing the properties ofthe Import source, and clicking on the Import Source button.

This command is available in FDTD only.

Syntax Description

asapimport( "sourcename"); Imports the fld file into the sourcename source. A filebrowser will open to select the file.This function does not return any data.

asapimport( "sourcename","filename");

Specify the file to open.

See AlsoSystem level , asapexport , asapload , addimportedsource , fileexists

7.1.37 matlabsave

Save workspace data to Matlab .mat data files.

Note: On some Windows computers with a newer version of MATLAB installed, the

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matlabsave script command will cause the GUI to crash. We are working to resolve theproblem. Until this issue is resolved, there are two potential solutions: - downgrade to MATLAB 2010B-use the matlabsavelegacy script command.

Syntax Description

matlabsave(""); Save all workspace variables to a .mat file that has thesame name as the simulation file.This function does not return any data.

matlabsave("filename"); Saves all workspace variables to the specified .mat file.

matlabsave("filename",var1, ..., varN);

Saves the specified workspace variables to the .mat file.

See Also System level , matlabput , matlabsavelegacy , matlabload , vtksave

7.1.38 matlabsavelegacy

Save workspace data to Matlab .mat data using a legacy Matlab file format required forMatlab version 7.2 and earlier. This file format does not support matrices larger than 2GB. The command syntax is the same as the standard matlabsave command. See matlabsave

for details.

See Also System level , matlabsave

7.1.39 matlabload

Load Matlab .mat data into workspace

Syntax Description

matlabload("filename"); Load to the workspace the data of the specified .mat file.

See Also System level , matlabput , matlabsavelegacy , matlabsave ,

7.1.40 matlab

Runs a MATLAB command from the Lumerical script prompt. This gives access toextended mathematical and visualization functionality from the Lumerical scriptenvironment. If the MATLAB script integration is not enabled, this function will return anerror.

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The first time a MATLAB function (matlab, matlabget or matlabput) is called, a MATLABsession will be started and a connection will be established with the Lumerical scriptingenvironment. Once this connection is established, MATLAB commands can be run usingthe matlab function. It is important to understand that the MATLAB and the Lumericalscript variable workspaces are completely separate and independent. A MATLABcommand cannot act on a variable defined in the Lumerical workspace, and vice-versa. Variables must be passed between the workspaces using the matlabget and matlabputfunctions. At any time you may examine the MATLAB workspace or interact with theMATLAB environment by typing commands at the MATLAB script prompt.

The output from the MATLAB commands will be printed at the Lumerical script prompt.One limitation of the matlab function is that no error reporting is provided to either theLumerical script prompt or the MATLAB prompt. MATLAB commands should be tested bytyping them directly into the MATLAB prompt before they are called from a Lumericalscript. The output buffer length is roughly 1e5 characters. Additional output will betruncated.

When you have a long sequence of MATLAB commands, you may find it more convenientto save them in a MATLAB m-file. Then, you can simply call the m-file by running a singlecommand.

Setup instructions and system requirements for the MATLAB script integration featurecan be found in the online Knowledge Base. See the Setup and Configuration section ofthe Installation Guide. Additional tips (particularly for plotting data in Matlab) can befound in the MATLAB section of the online User Guide.

Syntax Description

matlab("command"); command: a string containing one or more valid MATLABcommands.

matlab(" command_1 command_2");

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7.1.41 matlabget

Copies a variable from the MATLAB workspace to the script variable workspace. Theresulting variable will have the same name as the MATLAB variable, and will overwrite anyexisting variable with the same name. If the variable does not exist in MATLAB, thecommand will return an error. For more information, please see the matlab commanddescription.

Note: Matlab script integration must be enabled in order to use this command. For moreinformation on how to set this up see the Matlab script integration page.

Syntax Description

matlabget(var1, var2,...varN); The arguments to this command are one or more variablenames that refer to variables in the MATLAB workspace.This function does not return any data.

See AlsoSystem level , matlab , matlabput

7.1.42 matlabput

Copies a variable from the FDTD/MODE Solutions workspace to the MATLAB workspace.The resulting variable in the MATLAB workspace will have the same name as in FDTD/MODE Solutions, and will overwrite any existing variable with the same name. If the variabledoes not exist in the Lumerical workspace, the command will return an error.

For more information, please see the matlab command description.

Syntax Description

matlabput(var1, var2,...varN); The arguments to this command are one or more variablenames that exist in the Lumerical variable workspace.This function does not return any data.

See AlsoSystem level , matlab , matlabget

7.1.43 copytoclipboard

Copies the selected objects into the system clipboard. Equivalent to 'Ctrl-C'.

Syntax Description

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copytoclipboard Copies selected objects to the system clipboard

See AlsoSystem level , pastefromclipboard , copy

7.1.44 pastefromclipboard

Paste the contents of the system clipboard into the layout environment. Equivalent to 'Ctrl-V'.

Syntax Description

pastefromclipboard Paste contents of system clipboard

See AlsoSystem level , copytoclipboard , copy

7.1.45 debug

Opens the debug utility window.

This command is available in FDTD only.

Syntax Description

debug; Opens the debug utility window.


7.1.46 vtksave

The script command vtksave saves a Lumerical dataset into the VTK format. The commandonly saves rectilinear and unstructured datasets. The “filename” will have .vtr appended forrectilinear dataset, .vtu appended for unstructured dataset. The freely available datavisualization program Paraview can then be used to create sophisticated plots of your data.

Syntax Description

vtksave(“filename”, dataset); Save the dataset in vtk file of the name specified.

See Also System level , datasets , rectilineardataset , matlabsave , data visualization withParaView (User Guide)

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7.1.47 lookupread

Finds the nearest extracted value from a file containing a lookup table of design andextracted parameters.

Syntax Description

out = lookupread (filename,table,design,extracted);

Finds the nearest extracted value from a file containing alookup table of design and extracted parameters.Parameter table is the name of the lookup table locatedinside the file, design is a cell containing multiplestructures that define the design parameters to search,and extracted is the name of the parameter to beextracted. It will return the value located at the nearestdesign parameters.

See AlsoSystem level , lookupclose , lookupopen , lookupwrite

7.1.48 lookupopen

Opens a file to write a lookup table.

Syntax Description

lookupopen (filename,table); Opens a file to write a lookup table. This command isrequired before any calls to lookupwrite can be made.

See AlsoSystem level , lookupclose , lookupread , lookupwrite

7.1.49 lookupclose

Closes a file previously created with a lookupopen command.

Syntax Description

lookupclose (filename); Closes a file previously created with a lookupopencommand. This command is required in order to close anyfile open by lookupopen.

See AlsoSystem level , lookupopen , lookupread , lookupwrite

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7.1.50 lookupwrite

Writes to a lookup table a design and an extracted parameter pair.

Syntax Description

out = lookupwrite (filename, ,design, extracted);

Writes to a lookup table a design and an extractedparameter pair. The design and extracted parameters arecells that contain multiple structures, allowing for mappingbetween multiple design and extracted parameters. Thisfunction can be called multiple times, for each call thedesign and extracted parameters will be appended to thecurrent file. This function must be called after lookupopenand before lookupclose.

See AlsoSystem level , lookupclose , lookupopen , lookupread

7.2 Manipulating variablesThe following commands are used to create and access variables.

Command Description

= Assignment operator.

: Array operator.

[] Create matrix.

% Create variable with space in the name

linspace Creates a linear spaced array.

matrix Creates a matrix filled with zeros.

randmatrix Creates a matrix with all elements randomly setbetween 0 and 1

randnmatrix Creates a matrix with all elements randomlydistributed with mean 0 and standard distribution 1.

histogram Create a matrix containing the histogram count of ayield analysis result.

meshgridx Create a 2D meshgrid in x direction.

meshgridy Create a 2D meshgrid in y direction.

meshgrid3dx Create a 3D meshgrid in x direction.

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meshgrid3dy Create a 3D meshgrid in y direction.

meshgrid3dz Create a 3D meshgrid in z direction.

meshgrid4d Create a 4D meshgrid in any direction

clear Clears all stored script variables from memory.

workspace Returns a string of all the currently defined scriptingvariables.

Matrix elements How to assign and access matrix elements.

Matrix operations Describes how operators and functions act onmatrices.

Pre-defined constants List of pre-defined constants.

eye Creates identity matrix

struct Creates unstructured dataset

cell Creates cell array variable

The following commands are used to create, access and manipulate datasets. For anintroduction to datasets, see the dataset introduction page.

Command Description

rectilineardataset Creates an empty rectilinear dataset associated withthe coordinates x/y/z.

matrixdataset Creates an empty matrix dataset.

unstructureddataset Creates an empty unstructured dataset associatedwith the coordinates x/y/z and the connectivity matrix

addparameter Adds a parameter to an existing dataset.

addattribute Adds an attribute to an existing dataset.

getresult Gets the dataset results from a monitor or analyzer.

getparameter Get a parameter from an existing dataset.

getattribute Get an attribute from an existing dataset.

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7.2.1 =

Assignment operators.

Syntax Description

x = 5+2i; Assign a value to a variable.

See AlsoManipulating variables , ==

7.2.2 :

Array operator.

Syntax Description

x = 2 : 10; x will be an array of numbers that start at 2 and increaseby 1 for each consecutive number. The last entry will be<= 10. x will equal 2,3,...,9,10.

x = 6 : -1.5 : 2; x will be the array were the first element is 6, andconsecutive elements decrease by 1.5. All elements willbe >=2. In this example, the array will be [6, 4.5, 3].

See AlsoManipulating variables , linspace

7.2.3 []

Specify matrix element by element.

Command Description

x = [u11,...,u1N; u21,...,u2N;uM1,...,uMN]

Create an N by M matrix. Columns are separatedwith semicolons. Elements in a row are separatedwith commas. The entries can either be scalars ormatrices of compatible dimension.

See AlsoManipulating variables , linspace , matrix , Accessing and assigning matrixelements

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7.2.4 %

Used to create variables with spaced in the names.

Command Description

%variable with space% To create a variable name that contains spaces,such as "variable with space", put a percentage signbefore and after the variable name.

See AlsoManipulating variables

7.2.5 linspace

Creates a linearly spaced array.

Syntax Description

x = linspace(min,max,num); x will be an array with num elements, linearly spacedbetween min and max. If num is set to 1, then x will be theaverage of min and max.

See AlsoManipulating variables , : , []

7.2.6 matrix

Initialize a matrix. All elements are set to zero.

Syntax Description

x = matrix(i,j,k,....); Initializes an i x j x k x .... matrix.

See AlsoManipulating variables , linspace , []

7.2.7 randmatrix

Initialize a matrix. All elements are random numbers between 0 and 1.

Syntax Description

x = randmatrix(i,j,k,....); Initializes an i x j x k x .... matrix. The elements are all

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random numbers between 0 and 1.

See AlsoManipulating variables , matrix , rand , randreset

7.2.8 randnmatrix

Initialize a matrix. All elements are normally distributed random numbers with mean 0 andstandard distribution 1.

Syntax Description

x = randnmatrix(i,j,k,....); Initializes an i x j x k x .... matrix. The elements are allrandom normally distributed numbers with mean 0 andstandard deviation 1.

See AlsoManipulating variables , matrix , randn , randreset

7.2.9 histogram

Create a matrix containing the histogram count of a yield analysis result.

Syntax Description

out = histogram(y); Returns a matrix containing the histogram count of y.

out = histogram(y,n); Returns a matrix containing the histogram count of y,using n bins.

out = histogram(y,n,barplot);

Returns a matrix containing the histogram count of y,using n bins. If barplot is true (1), the histogram count isformatted for a bar plot.

See AlsoManipulating variables , histc

7.2.10 meshgridx

Create a 2D meshgrid in the x direction

Syntax Description

out = meshgridx(x,y); If x and y are single column (or single row vectors), ofdimension nX1 and mX1 respectively, the command

X = meshgridx(x,y);

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Will create a 2D matrix of dimension nXm where X(i,j)=x(i).

See AlsoManipulating variables , image , meshgridy , meshgrid3dx

7.2.11 meshgridy

Create a 2D meshgrid in the y direction

Syntax Description

out = meshgridy(x,y); If x and y are single column (or single row vectors), ofdimension nX1 and mX1 respectively, the command

Y = meshgridy(x,y); Will create a 2D matrix of dimension nXm where Y(i,j)=y(j).

See AlsoManipulating variables , image , meshgridx , meshgrid3dx

7.2.12 meshgrid3dx

Create a 3D meshgrid in the x direction

Syntax Description

out = meshgrid3dx(x,y,z); The 3D version of meshgridx and meshgridy.

See AlsoManipulating variables , meshgridx , meshgridy , meshgrid3dy , meshgrid3dz

7.2.13 meshgrid3dy

Create a 3D meshgrid in the y direction

Syntax Description

out = meshgrid3dy(x,y,z); The 3D version of meshgridx and meshgridy.

See AlsoManipulating variables , meshgridx , meshgridy , meshgrid3dx , meshgrid3dz

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7.2.14 meshgrid3dz

Create a 3D meshgrid in the z direction

Syntax Description

out = meshgrid3dz(x,y,z); The 3D version of meshgridx and meshgridy.

See AlsoManipulating variables , meshgridx , meshgridy , meshgrid3dx , meshgrid3dy

7.2.15 meshgrid4d

Create a 4D meshgrid in any direction.

Syntax Description

out = meshgrid4d(dim, x1,x2, x3, x4);

The 4D meshgrid function. dim specifies the dimension along which to create the gridx1,x2,x3,x4 are the position vectors in each direction

See AlsoManipulating variables , meshgridx , meshgridy , meshgrid3dy , meshgrid3dz

7.2.16 clear

Clears all stored workspace variables. This will not clear any simulation data stored in d-cards. The variables c, pi, eps0, mu0 will be reset to their default values.

Syntax Description

clear; Clears all workspace variables.This function does not return any data.

See AlsoManipulating variables , cleardcard

7.2.17 workspace

Returns a list of all the currently defined variables in the scripting workspace.

Syntax Description

out = workspace; Returns a string that lists all currently defined variables inthe workspace.

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Use ?workspace; to print this to the screen.


7.2.18 Accessing and assigning matrix elements

Accessing and assigning matrix elements.

Command Description

x = [u; v; w] Create a column vector. u,v,w can either be scalarsor matrices of compatible dimension.

x = [u, v, w] Create a row vector. u,v,w can either be scalars ormatrices of compatible dimension.

x(7) = 5; Set the 7th element of x to 5.

x(7) = y(2); Set the 7th element of x to the 2nd element of y.

x(3,1,8) = 3; Set an element of a multidimensional matrix to 3.

x(2:5,1) = 1:4; Set a sub-matrix of x to values 1:4. In theassignment A(I,...) = B, if B is not a scalar, the sub-matrix A(I,...) must be the same same size as B. If Bis a scalar, then all the values of the sub-matrix areset to B.

x(2:5,1) = 1; Set all the values in a sub-matrix of x to 1.

x = y(1:10,2,1:20); x is equal to a sub-matrix of y.

x = matrix(2,3);x(4)=7;

Multi-dimension matrices can be accessed with asingle index.

x=y(z); Indices stored in matrix (z) used to select elementsof matrix y. length(x) will equal length(z).


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7.2.19 Matrix operators

Almost all the scripting functions will act element by element on matrices. Single numbersare treated as matrices of dimension 1x1. The following table provides some examples.

Dimension ofx

Dimension ofy

Operation Dimension ofz

Value of z

1x1 N/A z = sin(x) 1x1 z11

= sin(x11

)

1x1 1x1 z = x * y 1x1 z11

= x11

* y11

10x10 1x1 z = x * y 10x10 Zij = x

ij * y

11

10x10 10x10 z = x * y 10x10 Zij = x

ij * y

ij

10x10 11x11 z = x * y Error Error


7.2.20 Pre-defined constants

Name Description

pi The number .

c The speed of light in a vacuum in m/s.

eps0 The permittivity of free space in SI units.

mu0 The permeability of free space in SI units.

h The Planck constant.

hbar The reduced Planck constant.

true Logical TRUE (1).

false Logical FALSE (0);

e The electron volt.


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7.2.21 matrixdataset

Creates an empty matrix dataset. Matrix datasets are used for data (attributes andparameters) that don't have any spatial dependence (i.e. Reflection vs frequency). Fordatasets that do have x/y/z spatial coordinates (i.e. electric fields), use rectilineardataset

.

Matrix datasets can be parameterized, and can contain an arbitrary number of attributes(see addattribute) and parameters (see addparameter) .

See Dataset introduction for more information.

Syntax Description

matrixdataset; Creates an empty dataset.

matrixdataset("name"); Creates an empty dataset with the name "name".

See Alsorectilineardataset , addattribute , addparameter , visualize , datasets ,getparameter , getattribute , matrixdataset , struct

7.2.22 rectilineardataset

Creates an empty rectilinear dataset that is associate with the x/y/z coordinates (ex. E andH fields). Like matrix datasets, rectilinear datasets can be parameterized, and can containan arbitrary number of attributes (see addattribute) and parameters (see addparameter)

.

See Dataset introduction for more information.For datasets that are not associated with the x/y/z coordinates (ex. transmission as afunction of frequency), see matrixdataset .

Syntax Description

rectilineardataset(x,y,z); Creates a empty rectilinear dataset associated with thecoordinates x/y/z.

rectilineardataset("dataset_name",x,y,z);

Creates a empty rectilinear dataset named"dataset_name" associated with the coordinates x/y/z.

See Alsorectilineardataset , addattribute , addparameter , visualize , datasets ,

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getparameter , getattribute , matrixdataset , struct

7.2.23 addparameter

Adds a parameter to an existing dataset.

Syntax Description

R.addparameter("p_name",p);

Adds the parameter p to the existing dataset R.

R.addparameter("p1_name",p1, "p2_name", p2);

Adds the interdependent parameter p1_name, p2_name tothe R dataset. The most common interdependent parameter is frequencyand wavelength. Parameters that are not interdependentmust be added separately.

See Alsorectilineardataset , addattribute , addparameter , visualize , datasets ,getparameter , getattribute , matrixdataset

7.2.24 addattribute

Adds an attribute to an existing dataset.

Syntax Description

R.addattribute("a_name", a); Adds the scalar attribute a to the dataset R.

R.addattribute("a_vector",a_1, a_2, a_3);

Adds the vector attribute a_vector to the existing datasetR. The components of the vector are a_1, a_2 and a_3

See Alsorectilineardataset , addattribute , addparameter , visualize , datasets ,getparameter , getattribute , matrixdataset

7.2.25 getparameter

Get a parameter from an existing dataset.

Syntax Description

?getparameter(R); Returns the names of all the parameters in the dataset R.

Parameter = R.getparameter("p");

Retrieves the parameter p from the existing dataset R. Theresult "Parameter" is a scalar matrix.

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Parameter = getparameter(R,"p");

Retrieves the parameter p from the existing dataset R. Theresult "Parameter" is a scalar matrix.

See Alsomatrixdataset , rectilineardataset , "." operator , getresult , getattribute ,visualize , datasets

7.2.26 getattribute

Get an attribute from an existing dataset.

Syntax Description

?getattribute(R); Returns the names of all the attributes in the dataset R.

Attribute = R.getattribute("a");

Retrieves the attribute a from the existing dataset R. Theresult "Attribute" is a scalar matrix.

Attribute = getparameter(R,"a");

Retrieves the attribute a from the existing dataset R. Theresult "Attribute" is a scalar matrix.

See AlsoDataset introduction , matrixdataset , rectilineardataset , "." operator , getresult

, getparameter , visualize , datasets

7.2.27 eye

The script command eye creates a 2D identity matrix.

Syntax Description

I = eye; Returns a 1x1 matrix, value 1.0.

I = eye(n); Returns nxn identity matrix.

I = eye(n,m); Returns nxm matrix with ones on main diagonal

See AlsoDatasets , matrixdataset , rectilineardataset , matlab , matrix

7.2.28 Datasets

Introduction to Lumerical datasetsLumerical datasets are structured data objects that collect a set of related matrices into asingle convenient object. To introduce this concept, we'll start by providing two examples. Additional information follows.

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Page contentsExample 1) – Reflection vs radius and heightExample 2) – Electric field data from a monitorAttributes and parametersWhat is in a dataset? Icons and the '?' operatorAccessing data in a dataset: the dot '.' operatorDataset types: matrixdataset and rectilineardatasetOperations on datasetsScalar and vector attributes

Example 1) – Reflection vs radius and height (matrix dataset)

Suppose you have a parameter sweep thatmeasures the reflection from a particle as afunction of particle radius and height.Saving this information generally requires 3matrix variables. The 2D matrix R containsthe reflection value from each simulation,while the 1D vectors radius and heightcontain the associated position values.

A dataset object can be used to collect allthree matrices into a single datasetvariable.

The following script code generates some example data, creates a R(radius,height)dataset, and finally creates several plots of the data.

# create example resultsradius = 0:10; height = 1:0.1:3;reflection = randmatrix(length(radius),length(height));

# create Reflection datasetR = matrixdataset("R"); # initialize datasetR.addparameter("radius",radius); # add radius parameterR.addparameter("height",height); # add height parameterR.addattribute("R",reflection); # add reflection attribute

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# plot dataimage(radius,height,reflection); # use original matricesimage(R.radius,R.height,R.R); # use dataset

# send dataset to visualizervisualize(R);

Example 2) – Electric field data from a monitor (rectilinear dataset)

Field monitors in FDTD and MODESolutions are used to calculate and savespatial electric field data. The raw electricfield data within the monitor is distributedbetween several matrices: Each vector fieldcomponent is stored in a matrix (Ex, Ey,Ez), and the four associated positionvectors (x,y,z,f) are also stored as separatematrices.

A dataset can be used used to collect all ofthis information into a single datasetvariable. The figure to the right shows thethree matrices Ex, Ey, Ez that store eachcomponent of the electric field. It alsoshows the associated position vectors x, y,z. All of this information can be storedwithin a single dataset variable.

Note: The electric field matrices usuallyhave a 4th dimension (time or frequency),but this dimension is not included in thefigure due to the difficulty of graphicallyrepresenting a 4th dimension!

The following script code shows how to get the raw data from a frequency monitor inFDTD Solutions (using getdata), and how to manually create a dataset from that data. Italso shows how to directly get the electric field dataset from the monitor in a singlecommand (using getresult). The final section shows how to create a few plots of the data

# monitor namem="monitor";

# get individual data elements with getdata

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x=getdata(m,"x");y=getdata(m,"y");z=getdata(m,"z");f=getdata(m,"f");Ex=getdata(m,"Ex");Ey=getdata(m,"Ey");Ez=getdata(m,"Ez");

# manually create the electric field dataset from the raw data# initialize dataset and provide spatial position vectorsE_manual = rectilineardataset("E_manual",x,y,z);

# add additional parameter: frequencyE_manual.addparameter("lambda",c/f,"f",f);

# add vector electric field attributeE_manual.addattribute("E",Ex,Ey,Ez);

# all of the above commands can be avoided with a singlegetresult commandE_fromMonitor = getresult(m,"E");

# plot Ex(x,y) at the first z value and first frequency pointto_plot = pinch(pinch(Ex,4,1),3,1); # use original matricesimage(x,y,to_plot); # use original matrices to_plot = pinch(pinch(E_manual.Ex,4,1),3,1); # use datasetimage(E_manual.x,E_manual.y,to_plot); # use dataset

# Plot the entire dataset with the Visualizervisualize(E_manual);

Attributes and parametersAttribute: The actual data of a dataset. In the examples above, the reflection R and electricfield Ex, Ey, Ez were the Attributes of the dataset.Parameter: The associated position vectors of a dataset. In the above examples, radius,height, x, y, z, and f were the parameters.

When creating datasets, the size of the attribute matrices must be consistent with thelengths of the associated parameters matrices.



What is in a dataset? Icons and the '?' operatorThe Results view and Script workspace windows provide a list of current monitor resultsand script variables. Different icons are used for each type of variable (dataset, matrix,string, unstructured data). For datasets, the preview column provides a list of theattributes and parameters in the dataset. In the screenshot below, the 'E' dataset containsone attribute (E) that is a function of 4 parameters (x,y,z, lambda/f).

The '?' operator can be used to output the same information to the script prompt. ?E_field = getresult("monitor","E");> E vs x, y, z, lambda/f

To output the actual attribute or parameter values, do something like:?E_field.x; # output the 'x' position vector> result: > -6.58393e-006 > -6.5442e-006 > -6.50447e-006 > .....

Accessing data in a dataset: the dot '.' operatorIndividual matrices stored in the dataset can be accessed with the dot '.' operator. Forexample, to get the raw x, y, and Ex data from an Electric field dataset, do something like: x = E_field.x;y = E_field.y;Ex = E_field.Ex;

Dataset types: matrixdataset and rectilineardataset

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Data without spatial parameters (such as example 1) will use matrix datasets.Data with spatial information from a rectilinear grid (such as the FDTD mesh) will use rectilinear datasets.

Operations on datasetsDatasets are primarily intended to be a convenient way to manage and store a collection ofrelated data. It is not possible to apply mathematical operations, such as addition, directlyto dataset objects. Instead, the dot operator must be used to get the desired data into amatrix. The operation can then be applied to the matrix. You may choose to create a newdataset to store the result, or you may simply keep the result as a standard matrix.

Scalar and vector attributesIt is possible to add both scalar and vector attributes to datasets.

ScalarThe command R.addattribute("R",reflection); # add reflection attribute

adds a scalar quantity 'R' to a dataset with the same name. To access the 'R' raw data,use:R.R;

VectorThe command E.addattribute("E",Ex_raw,Ey_raw,Ez_raw); # add vector E fieldattribute

adds a vector quantity 'E' to a dataset with the same name. In this case, we can accessthe raw 'E' data in the following ways:E.Ex; # get Ex componentE.Ey; # get Ey componentE.Ez; # get Ez componentE.E2; # get |E|^2E.E; # get all components in a single matrix. An extradimension of length 3 will be added to the matrix, for eachvector component.


7.2.29 struct

The script command struct adds an unstructured dataset. Any data type (such as matrix,string, dataset) can be added to struct objects.

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Syntax Description

a = struct; Creates an unstructured dataset.

a.a = "string"; Adds a string field to the structure.

a.b = matrix(5,5); Adds a field of matrix of 5x5 to the structure.

See AlsoDatasets , matrixdataset , rectilineardataset , cell

7.2.30 cell

The script command cell creates a cell array variable with specified number of elements.The cell array element can be any data type, such as matrix, string, and dataset.

Syntax Description

a = cell(n); Creates a cell array with n elements.

a{n} = "string"; Adds a string to the specified element of the cell array.

a{n} = matrix(5,5); Adds a field of matrix of 5x5 to the specified element of thecell array.

See AlsoDatasets , matrixdataset , rectilineardataset , struct , splitstring

7.2.31 unstructureddataset

Unstructureddataset script command creates an empty dataset that is associated witharbitrary x/y/z coordinate in space, and with additional matrix, a connectivity matrix toconnect them. The connectivity matrix comes after x, y, and z. Like rectilinear datasets,unstructured datasets can be parameterized, and can contain an arbitrary number ofattributes (see addattribute) and parameters (see addparameter) .

See Dataset introduction for more information.For datasets that are not associated with the x/y/z coordinates (ex. transmission as afunction of frequency), see matrixdataset .

Syntax Description

unstructureddataset(x,y,z,C);

Creates a empty rectilinear dataset associated with thecoordinates x/y/z and a connectivity matrix to connect

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them.


7.3 OperatorsStandard mathematical and string operators.

Algebraic operators

Command Description

* Multiplication. Ex: y = x * z;

/ Division. Ex: y = x / z;

+ Addition. Ex: y = x + z;

- Subtraction. Ex: y = x – z;

- Negative. Ex: y = -x;

^ Power. Ex: y = x 3;In expression A^B, if B is complex, the phase of A isevaluated from - to .

Logical and relational operators

Command Description

== Comparison.

almostequal Almost equal comparison operator.

!= Not equal.

<= Less than or equal to.

>= Greater than or equal to.

< Less than.

> Greater than.

& AND.

and AND.

| OR.

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or OR.

! NOT.

~ NOT.

Dataset operators

Command Description

. Retrieve the parameters and attributes of datasets.

String operators

Command Description

" Create a string variable.

' Create a string variable.

+ Add strings

endl end of line character.

Output to screen

Command Description

? Display output on screen.

# script file comments Comment script files with #

7.3.1 .

The dot operator can be used to retrieve the parameters and attributes of datasets.

Syntax Description

result = A.result; Retrieves the parameter or attribute "result" from theexisting dataset A. The result is a scalar matrix.

See Alsomatrixdataset , rectilineardataset , getparameter , getattribute , visualize

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7.3.2 *

Multiplication. When applied to matrices, this operator does simple element by elementmultiplication, not matrix multiplication.

Syntax Description

y = x * z; Multiply x and z.

See AlsoOperators , * , / , + , - , ^ , mult

7.3.3 /

Division.

Syntax Description

y = x / z; Divide x by z.

See AlsoOperators , * , / , + , - , ^

7.3.4 +

Addition.

Syntax Description

y = x + z; Add x and z.

y = string1 + string2; Concatenate strings together.


7.3.5 -

Subtraction, or negative.

Syntax Description

y = x - z; Subtract z from x.

y = -x; Negative

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7.3.6 ^

Power. In expression A^B, if B is complex, the phase of A is evaluated from - to .

Syntax Description

y = x 3; x cubed.

See Also Operators , * , / , + , - , ^

7.3.7 ==

Logical comparison. This operators can be used with complex numbers and strings.

Syntax Description

out = y == x; Returns 1 if x and y are equal. Returns 0 otherwise.

See AlsoOperators , = , almostequal , != , <= , >= , < , > , & , and , |, or , ! , ~

7.3.8 almostequal

Almost equal comparison operator. When using floating point numbers (rather thanintegers), two values that are meant to be equal may not be exactly equal due to roundingerrors that are always present in floating point calculations. In such cases, the almostequal function can be useful.

Syntax Description

out = almostequal(A, B); Returns 1 if A - B is less than or equal to A + B /2*1e-15. Returns 0 otherwise.

out = almostequal(A, B,relative diff);

Returns 1 if A - B is less than or equal to A + B /2times relative diff. Returns 0 otherwise.

out = almostequal(A, B,relative diff, absolute diff);

Returns 1 if A - B is less than or equal to A + B /2times relative diff or if A - B is less than or equal toabsolute diff. Returns 0 otherwise.

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See AlsoOperators , = , == , != , <= , >= , < , > , & , and , | , or , !

, ~

7.3.9 !=

Not equal to comparison operator. Returns 1 if values are not equal. Returns 0 if valuesare equal. This operator can be used in matrix operations. This operators can be usedwith complex numbers.

Syntax Description

out = a!=b; If a is not equal to b, then out equals 1. Otherwise outequals 0.

See AlsoOperators , == , almostequal , <= , >= , < , > , & , and , | , or

, ! , ~

7.3.10 <=

Logical less than or equal to. Imaginary components of x and y are ignored.

Syntax Description

out = y <= x; Less than or equal to.

See AlsoOperators , == , != , almostequal , >= , < , > , & , and , | , or

, ! , ~

7.3.11 >=

Logical greater than or equal to. Imaginary components of x and y are ignored.

Syntax Description

out = y >= x; Greater than or equal to.

See AlsoOperators , == , != , <= , almostequal , < , > , & , and , | , or

, ! , ~

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7.3.12 <

Logical less than. Imaginary components of x and y are ignored.

Syntax Description

out = y < x; Less than.

See AlsoOperators , == , != , <= , >= , almostequal , > , & , and , | , or

, ! , ~

7.3.13 >

Logical greater than. Imaginary components of x and y are ignored.

Syntax Description

out = y > x; Greater than.

See AlsoOperators , == , != , <= , >= , < , almostequal , & , and , | , or

, ! , ~

7.3.14 &

Logical AND. Imaginary components of x and y are ignored.

Syntax Description

out = y & x; If the real part of either or both of x,y are zero, then return0. Otherwise return 1.

y and x; Same as &.

See AlsoOperators , == , != , <= , >= , < , > , & , and , | , or , ! , ~

7.3.15 and

Logical AND. Imaginary components of x and y are ignored.

Syntax Description

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out = y & x; If the real part of either or both of x,y are zero, then return0. Otherwise return 1.

y and x; Same as &.


7.3.16 |

Logical OR. Imaginary components of x and y are ignored.

Syntax Description

out = y | x; If the real part of either or both of x,y is non-zero, thenreturn 1. Otherwise return 0.

y or x; Same as |.


7.3.17 or

Logical OR. Imaginary components of x and y are ignored.

Syntax Description

out = y | x; If the real part of either or both of x,y is non-zero, thenreturn 1. Otherwise return 0.

y or x; Same as |.


7.3.18 !

Logical NOT operator. If a value is 0, then NOT returns 1. For all other values, NOT returns0. NOT(A) is equivalent to A==0, where == is the comparison operator.

Syntax Description

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out = !a; applies logical not operator to a

out = ~a; applies logical not operator to a


7.3.19 ~

Logical NOT operator. If a value is 0, then NOT returns 1. For all other values, NOT returns0. NOT(A) is equivalent to A==0, where == is the comparison operator.

Syntax Description

out = !a; applies logical not operator to a

out = ~a; applies logical not operator to a


7.3.20 "

String operator. Strings can be created with single or double quotes.

The following escape sequences are recognized when creating strings with double quotes:\" double quotes in string\n newline (linefeed) character in string\\ backslash in string

Syntax Description

out="my string"; use double quotes to create strings

NOTE: Literal backslashes and double quotesIt is always possible to create a literal backslash in a string with \\. However, \ alsoresults in a literal backslash, IF it it will not be interpreted as part of an escape sequence(\n, \", \\). This note is important when storing paths in strings.

Suppose we want to create the string C:\Program Files\Lumerical. The following

three commands are valid and equivalent:mystring = 'C:\Program Files\Lumerical'; # use single quotes

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mystring = "C:\Program Files\Lumerical"; # use double quotesmystring = "C:\\Program Files\\Lumerical"; # use double quotesand \\ escape character

However, suppose we want to create the string C:\Program Files\Lumerical\.

The only difference is the additional backslash at the end of the string. The following twocommands are valid and equivalent:mystring = 'C:\Program Files\Lumerical\'; # use singlequotesmystring = "C:\\Program Files\\Lumerical\\"; # use doublequotes and \\ escape character

The other potential command, where we use a single backslash, is not valid syntax andwill result in an error.mystring = "C:\Program Files\Lumerical\"; # use doublequotes

The problem is that the script interpreter will interpret the final \" as an escape characterfor a literal double quote, rather than as a single backslash and a closing double quote. When interpreted this way, the command results in a syntax error because there is nodouble quote character closing the string.

See AlsoOperators , ' , num2str , + , endl , write , eval

7.3.21 '

String operator. Strings can be created with single or double quotes.

The following escape sequences are recognized when creating strings with single quotes:'' single quote in string (two single quote characters)

Syntax Description

out='my string'; use single quotes to create strings

See AlsoOperators , " , num2str , + , endl , write , eval

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7.3.22 endl

Add an end of line character to a string

Syntax Description

out = "line1"+endl+"line2"; Add an end of line character to the string.

See AlsoOperators , num2str , + , " , write

7.3.23 ?

Print output to the screen. Use the format script command to change the precision of theoutput.

Syntax Description

?command; Displays the output of the command on the screenThis function does not return any data.

See AlsoSystem level , write , format , #

7.3.24 comments

Use the # character to comment script files. Anything after the # character is ignored. Thecomments are not displayed when the script file is run. Comments can not be used whentyping commands directly into the script prompt.

Syntax Description

x=1; # set x to 1 Anything after the # character is ignored.


7.4 FunctionsStandard mathematical and matrix functions.

Trigonometric and complex

Command Description

sin Trigonometric sin function.

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cos Trigonometric cos function.

tan Trigonometric tan function.

asin Inverse trigonometric sin function.

acos Inverse trigonometric cos function.

atan Inverse trigonometric tan function.

atan2 Same as atan, but returns angle in correct quadrant.

real Returns the real part of variable

imag Returns the imaginary part of variable

conj Complex conjugate

abs Absolute value

angle Phase of a complex number.

unwrap Removes phase difference of more than 2

Logarithmic, exponential and power

Command Description

log The natural logarithm. Input can be complex ornegative.

log10 The log, base 10. Input can be complex or negative.

sqrt The square root.

exp The exponential.

Matrix functions

Command Description

size Returns the dimensions of a matrix.

length Returns the total number of elements in a matrix.

pinch Remove singleton dimensions from a matrix.

sum The sum of a matrix.

max The max value in a matrix.

min The min value in a matrix.

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dot The dot product of two vectors.

cross The cross product of two vectors.

flip Flip a matrix in one dimension.

interp Linear interpolation function.

spline Cubic spline interpolation.

integrate Integrate a matrix.

integrate2 Integrate a matrix, ignore singleton dimensions.

find Find values that satisfy a condition in a matrix.

findpeaks Find peaks in a matrix.

transpose Transpose a matrix.

ctranspose Transpose a matrix, and do complex conjugate.

mult Perform matrix multiplication of two or morematrices.

reshape Reshape the matrix to have different dimensionsconserving the overall product of the dimensions.

eig Calculate the eigenvalues and/or eigenvectors of amatrix.

permute Rearrange the dimensions of a matrix.

inv Calculate the inverse of a matrix.

mean Return the mean value of a matrix

var Returns the variance

std Returns the standard deviance

mapfind Returns a string value associated to specified point,given a file containing a map of values to a string

See alsoManipulating variables

String functions

Command Description

num2str Convert number to a string.

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str2num Convert a string into a floating point number.

eval Execute string containing Lumerical scriptinglanguage.

feval Run a Lumerical script file.

length Returns the total length of the string.

substring Returns a substring of a string, as a specifiedposition and length.

findstring Returns the position of a substring in a string.

replace Replaces a part of a string with another, at aspecified position.

replacestring Replaces all instances of a substring with anotherstring.

splitstring Split a single long string into a cell (string) arraybased on a delimiting character.

Frequency and time-domain

Command Description

fft Fast Fourier transform.

fftw Returns the angular frequency vector.

fftk Returns the spatial wavevector kx.

invfft Inverse fft.

czt Chirped z-transform.

Line and polygon functions

Command Description

polyarea Returns the area of a polygon.

centroid Returns the center of mass of a polygon.

polyintersect Determines if two polygons intersect.

inpoly Determines if a series of points are inside our outsidea polygon.

polygrow Grows or shrinks a polygon by a specified amount.

polyand Combines two polygons into one with an and

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operation.

polyor Combines two polygons into one with an oroperation.

polyxor Combines two polygons into one with a xoroperation.

lineintersect Returns the intersection of line segments.

linecross Determines if line segments cross each other.

Miscellaneous

Command Description

ceil Round up.

floor Round down.

mod Modulus after division.

round Rounds to the nearest integer.

rand Returns a uniformly distributed random numberbetween 0 and 1.

lognrnd Returns a lognormal distributed random number.

randn Returns a normally distributed random number.

randreset Resets the random number seed.

finite Determines if a number is finite or NaN.

solar Returns the solar power spectrum

stackrt Calculates reflection and transmission of multi-layerstacks

all Returns 1 if all of the specified matrix entries arenonzero and returns 0 otherwise.

any Returns 1 if any of the specified matrix entries arenonzero and returns 0 otherwise.

quadtri Returns approximated integration (first orderquadrature) of data on a 2D finite element mesh.

precision Returns truncated value to a user specified precision.

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7.4.1 sin

Trigonometric sine function. Angle units are in radians. Function is defined for complexangles. Phase of a complex number is evaluated between - and .

Syntax Description

out = sin(x); Returns the complex sine of x.

See Also Functions , asin

7.4.2 cos

Trigonometric cosine function. Angle units are in radians. Function is defined for complexangles. Phase of a complex number is evaluated between - and .

Syntax Description

out = cos(x); Returns the complex cosine of x.

See Also Functions , acos

7.4.3 tan

Trigonometric tangent function. Angle units are in radians. Function is defined for complexangles. Phase of a complex number is evaluated between - and .

Syntax Description

out = tan(x); Returns the complex tangent of x.

See Also Functions , atan , atan2

7.4.4 asin

Inverse trigonometric sine function. Angle units are in radians. Function is defined forcomplex values. Phase of a complex number is evaluated between - and . If x iscomplex, or abs(x) > 1, the following equation is used: asin(x) = -i ln( ix + sqrt(1-x 2))

Syntax Description

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out = asin(x); Returns the complex arcsine of x.

See Also Functions , sin

7.4.5 acos

Inverse trigonometric cosine function. Angle units are in radians. Function is defined forcomplex values. Phase of a complex number is evaluated between - and . If x iscomplex, or abs(x) > 1, the following equation is used: acos(x) = -i ln( x + i sqrt( 1-x 2))

Syntax Description

out = acos(x); Returns the complex arccosine of x.

See Also Functions , cos

7.4.6 atan

Inverse trigonometric tangent function. Angle units are in radians. Function is defined forcomplex values. Phase of a complex number is evaluated between - and . If x iscomplex, or abs(x) > 1, the following equation is used: atan(x) = 0.5 i ln( (i+x)/(i-x) )

Syntax Description

out = atan(x); Returns the complex arctangent of x.

See Also Functions , atan2 , tan

7.4.7 atan2

Inverse trigonometric tangent function, calculates the arctangent of y/x, but returns theangle in the correct quadrant. Angle units are in radians. Function is defined for realvalues only.

Syntax Description

out = atan2(y,x); x,y must be real.

See Also

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Functions , atan , tan

7.4.8 real

Returns the real part of a number or matrix.

Syntax Description

out = real(x); Returns the real part of x.

See Also Functions , imag

7.4.9 imag

Returns the imaginary part of a number or matrix.

Syntax Description

out = imag(x); Returns the imaginary part of x.

See Also Functions , real , conj

7.4.10 conj

Returns the complex conjugate of a number or matrix.

Syntax Description

out = conj(x); Returns the complex conjugate of x.

See Also Functions , real , imag

7.4.11 abs

Returns the absolute value of a number or matrix.

Syntax Description

out = abs(x); Returns the absolute value of x.

See Also Functions , real , imag

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7.4.12 angle

Returns the angle or phase of a complex number or matrix in radians.

Syntax Description

out = angle(x); Returns the phase of x.

See Also Functions , real , imag , unwrap

7.4.13 unwrap

Removes changes of more than 2 from a 1D array. It can be useful after angle(x) to seephase without discontinuities.

The unwrap function is primarily intended for 1D arrays. Care must be taken when applyingit to matrices with more than one dimension.

Syntax Description

out = unwrap(x); Return the values of x without discontinuities.

See Also Functions , real , imag , angle

7.4.14 log

The natural logarithm. Input can be complex or negative.

Syntax Description

out = log(x); The natural logarithm. Input can be complex or negative.

See Also Functions , log10

7.4.15 log10

The log, base 10. Input can be complex or negative.

Syntax Description

out = log10(x); The log, base 10. Input can be complex or negative.

See Also Functions , log

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7.4.16 sqrt

The square root.

Syntax Description

out = sqrt(x); The square root.

See Also Functions , ^

7.4.17 exp

The exponential.

Syntax Description

out = exp(x); The exponential.

See Also Functions , log , ^

7.4.18 size

Returns the size of a matrix.

Syntax Description

y = size(x); y is a matrix which shows the dimensions of x.

See Also Functions , length , flip , transpose

7.4.19 length

Returns the number of elements in a matrix. If the argument is a string, it will return thelength of the string.

Syntax Description

y = length(x); y the number of elements in a matrix. For example, if x isan n by m matrix, y = length( x ) = n * m.

See AlsoFunctions , size , transpose , flip , substring , findstring , replace ,

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replacestring

7.4.20 pinch

Removes all singleton dimensions from a matrix.

Syntax Description

out = pinch(x); Removes all singleton dimensions. For example, if x is amatrix of dimension 1x1x1xM, then

y=pinch(x); will return a Mx1 matrix where

y(i) = x(1,1,1,i);

pinch(x,i); Removes a specified dimension. If x is an NxMxKxPmatrix then

y=pinch(x,2); will return an NxKxP matrix where

y(i,j,k) = x(i,1,j,k)

pinch(x,I,j); Removes a specified dimension but keeps a specific indexfor the dimension being removed. If x is an NxMxKxPmatrix then

y=pinch(x,2,4); will return an NxKxP matrix where

y(i,j,k) = x(i,4,j,k)

See AlsoFunctions , find , size , flip

7.4.21 sum

Sum of elements in a matrix.

Syntax Description

out = sum(x); Sum of all the elements in a matrix, over all dimensions.

out = sum(x,2); Sum x over the specified dimension.

See AlsoFunctions , integrate , mean

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7.4.22 max

The maximum value in a matrix. For complex numbers, only the real part is considered.

Syntax Description

out = max(x); The maximum value in a matrix.

See AlsoFunctions , min , abs , mean

7.4.23 min

The minimum value in a matrix. For complex numbers, only the real part is considered.

Syntax Description

out = min(x); The minimum value in a matrix.

See AlsoFunctions , max , abs , mean

7.4.24 dot

Dot product.

Matrix A, B must have the same number of elements. The dot product will be calculatedwith the following formula.

i

iBiAC )()(

Syntax Description

C = dot(A, B); Returns the dot product of A and B

See Also Functions , cross , * , length , size

7.4.25 cross

Vector cross product.

Matrix A, B must be the same size. The cross product will be computed on the firstdimension that has a size of 3. There must be at least one dimension with a size of 3.

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Assume that A,B are 2D matrices, where the second dimension contains the vectorcomponents. The size of the second dimension must be 3. Then the elements of C will becalculated with the standard cross product formulas.

)1,()2,()2,()1,()3,(

)1,()3,()3,()1,()2,(

)2,()3,()3,()2,()1,(

iBiAiBiAiC

iBiAiBiAiC

iBiAiBiAiC

Syntax Description

C = cross(A, B); Returns the cross product of A and B

See Also Functions , dot , * , length , size

7.4.26 eig

Find the eigen value and/or eigen vector of a matrix. The matrix has to be square.

Syntax Description

out = eig(A);out = eig(A, 1);

Returns the eigenvalues of matrix A.

out = eig(A, 2); Returns the eigenvectors of matrix A.

out = eig(A, 3); Returns both the eigenvalues and eigenvectors of matrixA.


, ~ , mult , permute , reshape , inv

7.4.27 mult

Perform matrix multiplication of two or more matrices. The dimensions of the matrices haveto match

Syntax Description

out = mult(A,B,...) Returns the matrix multiplication of matrices, A x B x C ...

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, ~ , eig , permute , reshape , inv

7.4.28 flip

Flip a matrix along one dimension.

Syntax Description

C = flip(A, dim); Flips the matrix A along the dimension dim.

See Also Functions , size , length , pinch , transpose , reshape , permute

7.4.29 permute

This function is a more general version of the transpose function. It allows matrixdimensions to be rearranged as needed.

Syntax Description

out = permute(A, [i,j,k, ...]) Returns a matrix with the same elements as A but withrearranged dimensions i,j,k, etc.


, ~ , eig , reshape , mult , inv , flip , transpose , size

7.4.30 reshape

Reshapes the matrix A to have the size i,j,k.The product of the specified dimensions,i*j*k*..., must be the same as that of the original matrix A.

Syntax Description

out = reshape(A, [i,j,k, ...]) Returns an array with the same elements as A butreshaped to have the size i by j by k by ...

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, ~ , eig , permute , mult , inv , flip , transpose , size

7.4.31 inv

Calculate the inverse of a matrix. The matrix has to be invertible.

Syntax Description

out = Inv(A) Returns the inverse of matrix A


, ~ , eig , mult

7.4.32 interp

Linear interpolation of a data set. The data can be complex.

Syntax Description

out = interp(Ex, xold,xnew);

Does a linear interpolation of a 1D function. Ex is existing dataxold specifies the points where Ex is sampledxnew specifies new point to interpolate the data.

The xnew does does not have to be within the bounds ofxold.

interp(Ex, xold, yold, xnew,ynew);

The 2D version of interp.

interp(Ex, xold, yold, zold,xnew, ynew, znew);


interp(Ex, xold, yold, zold,told, xnew, ynew, znew,tnew);


See Also Functions , spline

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7.4.33 interptri

The script command interpolates a data set from triangular to linear grid. The data can becomplex.

Syntax Description

out = interptri(tri, vtx,u, xi, yi,extrap_val);

Does a triangular to linear interpolation of a function andoutputs a PxQ array of interpolated values, z(xi,yi).

u is existing data of the finite element mesh (Nx1).xi (length P) / yi (length Q) specifies the points where uis to be sampled on the rectilinear mesh, in the x-direction and the y-directiontri is the elements of the triangular mesh taken from thesimulation region, the connectivity array, Mx3,containing row entries that index the three vertices of Mtrianglesvtx are the vertices of the triangular mesh, Nx2,containing row entries of (x,y) pairs, taken from thesimulation regionextrap_val(optional): if an interpolation point is outside ofthe finite element mesh, the point will be assigned thisvalue (default is Inf)

See Alsoquadtri

7.4.34 spline

Does a cubic spline interpolation of a data set.

Syntax Description

out = spline(Ex,xold,xnew); Cubic spline interpolation of a 1D function. Ex is existing dataxold specifies the points where Ex is sampledxnew specifies new point to interpolate the data.

The xnew does does not have to be within the bounds ofxold.

See Also Functions , interp157 171



7.4.35 integrate

Returns the integral over the specified dimension of a matrix.

Integrals over singleton dimensions will return zero (i.e. the area under a single point iszero). See integrate2 for an alternate behavior.

Syntax Description

out = integrate(A, n, x1); Integrates A over the nth dimension in the matrix. x1 is the corresponding position vector for that dimension.

out = integrate(A, d, x1,x2, ...);

Calculates the integral of A over the specified list ofdimension(s) d.d is a vector containing the dimensions over which tointegrate.xi are the position vectors corresponding to the dimensionsof A over which the integration is occurring. For example

power = integrate(A,1:2,x,y) will integrate A over an x-ysurface.

See Also Functions , integrate2 , max , min , interp , find , pinch , round ,getdata , sum , length

7.4.36 integrate2

Very similar to the standard integrate function, except that singleton dimensions areignored.

As described in the integrate function description, integrating over dimensions with a singlevalue (singleton dimensions) returns zero because the area under a single point is zero. Insome cases, particularly when you are not sure which dimensions are singleton, thisbehavior can cause difficulties. The integrate2 function automatically ignores alldimensions with a size of one, which avoids the problem of a zero valued integrals due tosingleton dimensions.

Syntax Description

out = integrate2(A, 1, x1); Integrates A over the first dimension in the matrix. x1 is the corresponding position vector.

out = integrate2(A, d, x1, x2,...);

Calculates the integral of A over the specified dimension(s)d.

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d is a vector containing the dimensions over which tointegrate.xi is the position vector corresponding to the dimensions ofA over which the integration is occurring. If any of the xivectors only have 1 element, integrate returns 0.For example

power = integrate2(A,1:2,x,y) will integrate A over an x-ysurface.

See Also Functions , integrate , max , min , interp , find , pinch , round ,getdata , sum , length

7.4.37 find

This function will search for entries in a matrix that meet some condition. The indices ofthose values are returned.For multi-dimensional matrixes, the find function will still return a single index. This isuseful when using the output from find in a loop.

Syntax Description

out = find(x,5e-6); Will return the index of x that corresponds to the closestvalue to 5e-6.

out = find(x>5); Will return indices of all values of x that are greater than 5.

See AlsoFunctions , pinch , findpeaks , integrate , length , size , mod ,meshgrid3dx , meshgrid3dy , meshgrid3dz

7.4.38 findpeaks

Returns the position of peaks in a matrix. A peak is defined as a data point that is largerthan its nearest neighbors.

Syntax Description

out = findpeaks(y); Returns the position of the peak with the largest value in y.The length of y must be at least 2. If no peak is found inthe data, a value of 1 is returned.

findpeaks(y,n); Returns a matrix containing the positions of the largest npeaks found in the data. The returned values are ordered

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from largest to smallest. The returned matrix is always ofdimension nX1. If less than n peaks are found, theremaining values of the returned matrix are 1.

See AlsoFunctions , find

7.4.39 transpose

Transpose a 1D or 2D matrix.

Syntax Description

y = transpose(x); If x is an N x M matrix, then y will be M x N, where theentries are y(j,i)=x(i,j).

See AlsoFunctions , ctranspose , reshape , flip , permute , size

7.4.40 ctranspose

Transpose a 1D or 2D matrix and take the complex conjugate of each element.

Syntax Description

y = ctranspose(x); If x is an N x M matrix, then y will be M x N, where the

entries are y(j,i)=x(i,j)*.

See AlsoFunctions , transpose

7.4.41 num2str

Convert an integer, floating point number, or matrix into a string. Use the format scriptcommand to change the precision of the output.

Syntax Description

out = num2str(x); Converts the number x into a string. x can also be a 1D or2D matrix.

See AlsoOperators , " , + , ? , endl , write , format ,str2num , findstring ,replace , replacestring , substring , eval

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7.4.42 str2num

Convert a string into a floating point number. Use the format script command to change theprecision of the output.

Syntax Description

out = str2num(string); Converts string into a number.

See AlsoOperators , " , + , ? , endl , write , format , findstring , replace ,replacestring , substring

7.4.43 eval

Execute string containing Lumerical scripting language.

Syntax Description

eval(string); Execute string containing Lumerical scripting language atthe Lumerical script prompt.This function does not return any data.

See AlsoOperators , feval , str2num , num2str

7.4.44 feval

Evaluates a string as script file. This function is useful for running script files that are not inyour path and files with spaces in the name.

Syntax Description

feval(filename); Execute string containing the name of a script file at theLumerical script prompt.This function does not return any data.

See AlsoOperators , eval , str2num , num2str

7.4.45 substring

Can be used to extract a substring from a string.

Syntax Description

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s1 = substring(s,pos); Returns a substring of s, starting at position pos to the endof s. The position pos can be 1 to length(s).

s1 = substring(s,pos,len); Returns a substring of s, starting at position pos, with lencharacters. If len is -1 (or any value less than 0) it returnsthe substring at position pos to the end of s. The defaultvalue of len is -1.

See AlsoFunctions , length , findstring , replace , replacestring , str2num , num2str

, splitstring

7.4.46 findstring

Returns the position of a given substring in a string.

Syntax Description

pos = findstring(s,s1); Returns the position of the first instance substring s1 in s.If s1 is not found in s, it returns -1.

pos = findstring(s,s1,p0); Returns the position of the first instance substring s1 in s,starting at position p0. If s1 is not found in s, starting fromp0, it returns -1.

See AlsoFunctions , length , substring , replace , replacestring , str2num , num2str

, splitstring

7.4.47 replace

Replaces a substring of a string with a new string.

Syntax Description

snew = replace(s,pos,len,s1);

Replaces len characters of s, starting at position pos, withthe string in s1. If len is 0, it will insert the string s1between pos-1 and pos. If len is -1 (or any values less than0) it will replace all remaining characters in s with s1,starting at pos. The position pos can be 1 to length(s).

See AlsoFunctions , length , substring , findstring , replacestring , str2num ,num2str , splitstring

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7.4.48 replacestring

Replaces a substring of a string with a new string.

Syntax Description

snew = replacestring(s,s1,s2);

Replaces all instances of s1 in s with s2.

See AlsoFunctions , length , substring , findstring , replace , str2num , num2str ,splitstring

7.4.49 splitstring

Split a long string into a series of substrings, where the substrings are stored in a cell (ie.string) array.

Syntax Description

S2 = splitsting(S1,endl); Split the string S1 into a series of strings, using the end ofline character as the delimiter between strings. S2 is acell array.

See AlsoFunctions , length , substring , findstring , replace , str2num , num2str ,cell , dir , getresult

7.4.50 fft

Compute the 1D, 2D or 3D Fast Fourier Transform (fft) of a matrix. In the 1D case thetransform is given by

)1)(1)(2

(

1

][)(][mn

N

iN

nxxw enEEfftmE

The fft, inverse fft and all associated functions have an option (option 1 below) that controlsthe format used to store the frequency domain data. When working with spectral data it isnot possible to switch between formats; there are no functions to convert between formats.This implies that if you use option 1=n to produce a spectrum with fft, then you must alsouse option 1=n if you want to pass that same spectral data to invfft. Similarly, if you useoption 1=n for fft, then you also need to use option 1=n with fftw to get the proper frequencyvector corresponding to your spectrum. invfft and fftk work in the same way.

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Syntax Description

out = fft(Ex); Returns the fast Fourier transform of Ex. Ex can be 1D, 2Dor 3D.

out = fft(Ex,option1,option2);

option1 This option controls the format used to store the frequencydomain data. The options are:

1 : the standard fft (zero frequency is at the first elementof the matrix). 2 : zero frequency is the first element, but only data upto and including the Nyquist frequency is stored. Thisoption is only useful for real valued, 1D time/spatialsignals.3 : the fft is shifted so zero frequency is the centralelement of the spectrum (precisely, this means the zerofrequency point is at element floor(N/2 + 1), where N isthe number of samples).

option2 This option is either a 1, 2 or 3 element vector dependingon whether Ex is 1D, 2D or 3D. For each dimension,specify a value of either 0, 1 or N to obtain the desired 0padding options.

0: no zero padding1: zero padding up to the next power of 2 longer than thelength of Ex (default)N: zero pad up to length N if N > length(Ex), wherelength of Ex is the length in a specific dimension. If N <=length(Ex), it will zero pad up to the next power of 2longer than the length of Ex. For the fastest results, Nshould be a power of 2 and can be entered, for example,as 2 12.

Note: FFT ConventionsThere are different, but equivalent conventions for defining Fourier transforms. Lumericaldefines the forward FFT using a positive sign in the exponential term, and the inverse FFT using a negative sign in the exponential term. However, some other packages (e.g.MATLAB) use the opposite convention, with a negative sign in the exponential for theforward FFT and a positive sign in the exponential for the inverse FFT. To convert betweenthe different FFT conventions, switch the invfft and fft and rescale the results. For a signaly with N elements this can be done as follows:

Reference Guide180


Lumerical MATLAB

fft(y,1,0)invfft(y,1,0)

ifft(y)*N fft(y)/N

See Also Functions , invfft , fftw , fftk , czt

7.4.51 fftw

Returns the angular frequency vector corresponding to time vector t.

)1(,,02

)( MMdt

tfftww

,where M=length(t).

fftw and all related functions have an option (option 1 below) that controls the format used tostore the frequency domain data. When working with spectral data it is not possible toswitch between formats; there are no functions to convert between formats. This impliesthat if you use option 1=n to produce a spectrum with fft, then you must also use option1=n if you want to pass that same spectral data to invfft. Similarly, if you use option 1=nfor fft, then you also need to use option 1=n with fftw to get the proper frequency vectorcorresponding to your spectrum. Invfft and fftk work in the same way.

Syntax Description

out = fftw(t); Returns the angular frequency vector corresponding to timevector t.

fftw(t,option1,option2); Option1 1 : the standard fft (default) 2 : frequencies above the Nyquist frequency areremoved 3 : the fft is shifted so both positive and negativefrequencies are seen

Option20: no zero padding1: zero padding up to the next power of 2 longer than thelength of Ex (default)N: zero pad up to length N if N > length(t). If N <= length(t), it will zero pad up to the next power of 2 longer thanthe length of t. For the fastest results, N should be apower of 2 and can be entered, for example, as 2 12.

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See Also Functions , fft , fftk , invfft

7.4.52 fftk

Returns the spatial wavevector kx associated with a fourier transform of a function of x.

)1(,,02

)( MMdx

xfftkk

,where M=length(x).

fftk and all related functions have an option (option 1 below) that controls the format used tostore the frequency domain data. When working with spectral data it is not possible toswitch between formats; there are no functions to convert between formats. This impliesthat if you use option 1=n to produce a spectrum with fft, then you must also use option1=n if you want to pass that same spectral data to invfft. Similarly, if you use option 1=nfor fft, then you also need to use option 1=n with fftw to get the proper frequency vectorcorresponding to your spectrum. Invfft and fftk work in the same way.

Syntax Description

out = fftk(x); Returns the spatial wavevector kx associated with a fouriertransform of a function of x..

fftk(x,option1,option2); Option1 1 : the standard fft (default) 2 : frequencies above the Nyquist frequency areremoved 3 : the fft is shifted so both positive and negativefrequencies are seen

Option20: no zero padding 1: zero padding up to the next power of 2 longer than thelength of Ex (default)N: zero pad up to length N if N > length(x). If N <= length(x), it will zero pad up to the next power of 2 longer thanthe length of x. For the fastest results, N should be apower of 2 and can be entered, for example, as 2 12.

See Also Functions , fft , fftw , invfft

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7.4.53 invfft

Compute the 1D,2D or 3D inverse Fast Fourier Transform (fft) of a matrix. In the 1D casethe transform is given by

)1)(1)(2

(

1

][1

)(][mn

N

iN

nwwx enE

NEinvfftmE

The inverse fft, fft and all related functions have an option (option 1 below) that controls theformat used to store the frequency domain data. When working with spectral data it is notpossible to switch between formats; there are no functions to convert between formats. Thisimplies that if you use option 1=n to produce a spectrum with fft, then you must also useoption 1=n if you want to pass that same spectral data to invfft. Similarly, if you use option1=n for fft, then you also need to use option 1=n with fftw to get the proper frequency vectorcorresponding to your spectrum. Invfft and fftk work in the same way.

Syntax Description

out = invfft(x); Returns the inverse fast Fourier transform of x. x can1D,2D or 3D.

invfft(x,option1,option2); option1 This option controls the format used to store the frequencydomain data. The options are:

1 : the standard fft (zero frequency is at the first elementof the matrix). 2 : zero frequency is the first element, but only data upto and including the Nyquist frequency is stored. Thisoption is only useful for real valued, 1D time/spatialsignals.3 : the fft is shifted so zero frequency is the centralelement of the spectrum (precisely, this means the zerofrequency point is at element floor(N/2 + 1), where N isthe number of samples).

option2 This option is either a 1, 2 or 3 element vector dependingon whether Ex is 1D, 2D or 3D. For each dimension,specify a value of either 0, 1 or N to obtain the desired 0padding options.

0: no zero padding1: zero padding up to the next power of 2 longer than thelength of Ex (default)N: zero pad up to length N if N > length(Ex), where



length of Ex is the length in a specific dimension. If N <=length(Ex), it will zero pad up to the next power of 2longer than the length of Ex. For the fastest results, Nshould be a power of 2 and can be entered, for example,as 2 12.

See Also Functions , fft , fftw , fftk

7.4.54 czt

Returns the chirped z-transform of a set of data. The czt function is often more convenientthan the standard fft functions because you can specify an arbitrary range of k.

2,1

]2[]2[]1[]1[

][][

]2,1[)2,1,2,1,(]2,1[

][),,(][

nn

mknixmknixxxk

n

mknixxxk

ennEkkxxEcztmmE

enEkxEcztmE

Syntax Description

out = czt(Ex,t,w) Returns the chirped z-transform of Ex, function of t, ateach desired angular frequency w. Note that w must be alinearly spaced set of angular frequencies but can coverany range.

czt(Ex,x,y,kx,ky); The two dimensional chirped z-transform. kx and ky mustbe linearly spaced sets of wavenumbers but can cover anyrange.

See Also Functions , fft

7.4.55 polyarea

Returns the area of a polygon. The area is positive if the vertices are defined in a counter-clockwise direction, and negative if the vertices are defined in a clockwise direction.

The polygon vertices are contained in a single matrix of dimension Nx2 (or 2xN) where N>= 3. The second dimension represents the x,y positions. For example, a valid polygon isV = [ 0,0; 1,0; 1,1; 0,1];

Syntax Description

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out = polyarea(V); Returns the area of V. The sign of the area indicates if V isdefined in a counter-clockwise (positive) or clockwise(negative) direction.

See Also Functions , centroid , polyintersect , inpoly , polygrow , polyand , polyor

, polydiff , polyxor

7.4.56 centroid

Returns the center of mass of a polygon.


Syntax Description

out = centroid(V); Returns the center of mass of V, assuming uniformdensity. The output is a 2x1 matrix representing the x andy positions.

See Also Functions , polyarea , polyintersect , inpoly , polygrow , polyand , polyor


7.4.57 polyintersect

Determines if two polygons intersect.


Syntax Description

out = polyintersect(V1,V2); Returns0 if the polygons do not overlap0.5 if the polygons touch1 if they overlap2 if one polygon completely encloses the other

See Also Functions , polyarea , centroid , inpoly , polygrow , polyand , polyor ,

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polydiff , polyxor

7.4.58 inpoly

Determines if a point is inside our outside a polygon. The function is vectorized so it can beused to create a mesh of a polygon.


Syntax Description

out = inpoly(V,x,y); Returns a matrix of the same dimension of x with 1 if thecorresponding point is inside the polygon and 0 otherwise.The matrices x and y must have the same length, or one ofthem can be a singleton.

See Also Functions , polyarea , centroid , polyintersect , polygrow , polyand , polyor


7.4.59 polygrow

Returns a polygon that has grown or shrunk by the specified amount. The polygon is grownin a direction normal to every line segment.


Syntax Description

out = plygrow(V,dx); Returns a new polygon that has grown by dx. To shrink apolygon, use dx < 0.

See Also Functions , polyarea , centroid , polyintersect , inpoly , polyand , polyor


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7.4.60 polyand

Combines two polygons into one using a boolean and operation.


Syntax Description

V3 = polyand(V1,V2); Returns a new polygon, V3, that is the and of V1 and V2.

See Also Functions , polyor , polydiff , polyxor , polyarea , centroid , polyintersect

, inpoly , polygrow

7.4.61 polyor

Combines two polygons into one using a boolean or operation.


Syntax Description

V3 = polyor(V1,V2); Returns a new polygon, V3, that is the or of V1 and V2.

See Also Functions , polyand , polydiff , polyxor , polyarea , centroid , polyintersect

, inpoly , polygrow

7.4.62 polydiff

Combines two polygons into one by taking the difference.


Syntax Description

V3 = polydiff(V1,V2); Returns a new polygon, V3, that is V1-V2.

See Also Functions , polyand , polyor , polyxor , polyarea , centroid , polyintersect

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, inpoly , polygrow

7.4.63 polyxor

Combines two polygons into one using a boolean xor operation.


Syntax Description

V3 = polyxor(V1,V2); Returns a new polygon, V3, that is the xor of V1 and V2.

See Also Functions , polyand , polyor , polydiff , polyarea , centroid , polyintersect

, inpoly , polygrow

7.4.64 lineintersect

Returns the intersection points of lines in the x-y plane. Note that the intersection pointdoes not have to lie on the line segments themselves that define the lines. To see if the linesegments actually cross the command linecross should be used.

Line segments are contained in a single matrix of dimension 2*Nx2, where there are N linesegments. For example, the matrix L = [ 0,0; 1,1; 0,0, 0,1]; represents 2 lines segments,one from (0,0) to (1,1) and another from (0,0) to (0,1).

Syntax Description

out = lineintersect(L1,L2); Returns the intersection of the lines represented by thesegments in L1 and L2. L1 and L2 must have the samesize (2*N,2 for N line segments). The result is a sequenceof x,y points in the form Nx2 representing the intersectionsof the N lines. There are special cases when

The lines are parallel. In this case, the position returnedis (1.#INF,b). The value of 1.#INF can be tested for usingthe script commands finite. The value of b is 0 if the linesare not coincident and 1 if they are coincident.The points in a segment are degenerate, ie the same. Inthis case, the position returned is (1.#INF,b), where b is0, 1, 2 if the both line segments are degenerate, the firstis degenerate, or the second is degenerate respectively.

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See Also Functions , linecross , finite

7.4.65 linecross

Determines if line segments cross each other.

Line segments are contained in a single matrix of dimension 2*Nx2, where there are N linesegments. For example, the matrix L = [ 0,0; 1,1; 0,0, 0,1]; represents 2 lines segments,one from (0,0) to (1,1) and another from (0,0) to (0,1).

Syntax Description

out = linecross(L1,L2); Returns a matrix of dimension N which determines if the Nline segments in L1 and the N line segments in L2 cross.L1 and L2 must have the same size (2*Nx2 for N linesegments). The result is a matrix of length N that is 0 ifthe segments do not cross, 1 if they cross and 0.5 if theendpoint of one line touches another. Line segments thatare coincident and touch also return a value of 0.5

See Also Functions , lineintersect , finite

7.4.66 ceil

The ceil command rounds the input to the nearest integer greater than or equal to itself.

Syntax Description

out = ceil(X); Returns the nearest integer greater than or equal to X.

See AlsoFunctions , floor , mod

7.4.67 floor

The floor command rounds the input to the nearest integer less than or equal to itself.

Syntax Description

out = floor(X); Returns the nearest integer less than or equal to X.

See AlsoFunctions , ceil , mod

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7.4.68 mod

Modulus after division.

Syntax Description

out = mod(X,Y); Returns X - n.*Y where n = floor(X./Y) if Y is not equal to 0.The input X must be a real array or a real scalar. Y mustbe a real scalar.The following are true by convention:mod(X,0) = Xmod(X,X) = 0

See AlsoFunctions , floor , ceil

7.4.69 sign

Get the sign of a number.

Syntax Description

out = sign(data); Real valuessign = 0 for data=0sign = 1 for data>0sign =-1 for data<0

Complex valuessign = 0 for data=0+0isign = data/abs(data) for data!=0

See AlsoFunctions , floor , ceil

7.4.70 round

Rounds a number to the nearest integer.

Syntax Description

out = round(x); Rounds x to the nearest integer.

See AlsoFunctions

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7.4.71 rand

Generate a uniform random number between 0 and 1.

Syntax Description

out = rand; Generates a uniform random number between 0 and 1.

out = rand(min,max); Generates a random number between min and max. Bydefault, min and max are 0 and 1 respectively.

out = rand(min,max,option); option = 1: output is a double precision number betweenmin and max (default)option = 2: output is an integer between min and max.

See AlsoFunctions , randreset , randmatrix

7.4.72 lognrnd

Generate a lognormal distributed random number. This command is available inINTERCONNECT only.

Syntax Description

out = lognrnd (mean,stddev); Generates a lognormal distributed random number withuser defined mean value and standard deviation.

See AlsoFunctions , randreset , randn

7.4.73 randn

Generate a normally distributed random number. This command is available inINTERCONNECT only.

Syntax Description

out = randn; Generates a normally distributed random number withmean 0 and standard deviation 1.

out = randn(mean,stddev); Generates a normally distributed random number with userdefined mean value and standard deviation.

See AlsoFunctions , randreset , lognrnd , randnmatrix

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7.4.74 randreset

Resets the random number generator seed.

Syntax Description

out = randreset; Resets the random number seed based on the clock time.This function returns the random number seed that wasused.

out = randreset(seed); Set the seed to a specific value

See AlsoFunctions , rand , randmatrix

7.4.75 finite

The finite command returns 1 (true) if a value is finite. Numbers such as NaN or #1.INFreturn 0 (false).

Syntax Description

out = finite(x); Returns a matrix of the same size as x. The values are 1for values of x that are finite and 0 for values that are NaN.For example, finite(1/0) returns 0.

See AlsoFunctions

7.4.76 solar

Returns the solar power spectrum, in Watts/meter 2/meter. This command is available inFDTD and DEVICE.

The values are based on the global tilt values from the following link:http://rredc.nrel.gov/solar/spectra/am1.5/ASTMG173/ASTMG173.html

Syntax Description

out = solar(1); Returns the power of the solar spectrum as a function ofwavelength, in W/m 2/m

out = solar(0); Returns the corresponding wavelength vector, in m

See Also plot , integrate

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7.4.77 stackrt

Analytically calculates the reflection and transmission of a plane wave through a multi-layerstack. This function returns the fraction of transmitted and reflected power (Ts, Tp, Rs,Rp), and the complex reflection and transmission coefficients (ts, tp, rs, rp), for both S andP polarizations. All results are returned in a single dataset as a function of frequency andincidence angle (optional).

Note: Thickness of first and last layerIt is necessary to specify the thickness of each layer, including the first and last layers. Often, a thickness of zero can be used for these layers, meaning the results will becalculated just beyond the first and last interface. If a larger value is used, the results willbe calculated further from the interface. For non-lossy materials, this will not effect thereflected and transmitted power, but it will change phase of the complex coefficients.

Syntax Description

RT = stackrt(n,d,f); Arguments for a stack with Nlayers:n: Refractive index of each layer. Size is either Nlayers, orNlayers x length(f) if dispersive materials are involved.d: Thickness of each layer. Size is Nlayers. f: Frequency vector.

RT = stackrt(n,d,f,theta); theta: Angle vector, in degrees. Optional.

See Also Functions

7.4.78 mean

The mean value in a matrix is returned.

Syntax Description

out = max(a); The mean value of the matrix a is returned.

See Alsomax , min , abs , sum

7.4.79 all

The script command returns 1 if all of the specified matrix entries are nonzero and returns 0otherwise.

Syntax Description

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out = all(A); Will return 1 if all of the A matrix entries are nonzero andwill return 0 otherwise.

See Alsoany , almostequal

7.4.80 any

The script command returns 1 if any of the specified matrix entries are nonzero and returns0 otherwise.

Syntax Description

out = any(A); Will return 1 if any of the A matrix entries are nonzero andwill return 0 otherwise.

See Alsoall , almostequal

7.4.81 var

The script command returns the variance of all entries of the matrix specified, wherevariance is defined as,

N

iiN

x1

2

)(1

var

Syntax Description

out = var(A); Will return variance of all of matrix A, over all dimensions.

See Alsostd , mean

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7.4.82 std

The script command returns the standard deviation of the all entries of the matrix specified,where standard deviation is defined as,

N

iiN

x1

2

)(1

Syntax Description

out = std(A); Will return standard deviation of matrix A, over alldimensions.

See Alsovar , mean

7.4.83 mapfind

The script command returns the nearest value from a file containing a map of values to astring. It returns the string value located at the specified nearest point.

Syntax Description

out = mapfind (filename,x,y); Find the nearest value from a file containing a map ofvalues to a string. It l returns the string value located at thenearest point (x,y).

out = mapfind (filename,x,y,z);

Find the nearest value from a file containing a map ofvalues to a string. It returns the string value located at thenearest point (x,y,z).

out = mapfind (filename,x,y,z,w);

Find the nearest value from a file containing a map ofvalues to a string. It returns the string value located at thenearest point (x,y,z,w).

See Alsoreaddata , readdata

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7.4.84 quadtri

The script command approximates integration (first order quadrature) of data on a 2D finiteelement mesh.

Syntax Description

out = quadtri(tri,vtx,u); outputs a scalar, the integral of u on the finite elementmesh, where

tri: the connectivity array, Mx3, containing row entriesthat index the three vertices of M trianglesvtx: the vertex array, Nx2, containing row entries of (x,y)pairsu: the data on the finite element mesh (Nx1)

See Alsointerptri

7.4.85 expand

The script command returns the expansion coefficients between two arbitrary DFTmonitors. Typically, the reference monitor contains the modal fields for the expansion.

*11

*22

2

1*2

2

*21

2

1*2

2

*21

*5.0

*5.0

*25.0

*25.0

HESdP

HESdN

N

HESd

N

HESdb

N

HESd

N

HESda

For more detail on how to use this command, and how to interpret the results, please see Using Mode Expansion Monitors.

Syntax Description

expand('a','a_ref',x,y,z); outputs the expansion coefficients between the fields oftwo monitors

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a: the monitor name, of which expansion is performed a_ref: the reference monitorx/y/z: the displacement from the monitor a from thereference monitor a_ref

See AlsoAdding Objects , Using Mode Expansion Monitors, setexpansion , removeexpansion

, expand2

7.4.86 norm

The script command returns the natural norm induced by the L2-norm (Spectral Norm).

Syntax Description

out = norm(y); Returns y to the L2-norm, y is a matrix.

See AlsoFunctions

7.5 Loop and conditional statementsThe scripting language currently supports FOR loops and IF statements. Other controlstructures such as while loops or case statements must be constructed from these.

Command Description

for For loop.

if If statement.

while A for loop must be used. See the for loop section.

7.5.1 for

for loops allow some operations to be repeated a number of times. A while loop can beimplemented when using the three argument version of for.

Syntax Description

for(x=1:100) { ?x; } Single argument for loop.The loop will be sequentially executed for each valueof x.

for(x=1; x<= 100; x=x+1) { ?x;

Three argument for loop. x=1 at the start of the loop. The loop continues while

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} x <=100 and sets x=x+1 at each pass.

x=1;for(0; x<10; 0) { ?x; x=x+1;}

This is equivalent to a while loop that will executewhile x<10.

See Also Loops , if

7.5.2 if

The scripting language supports if statements in the following forms:

Syntax Description

if(x < 5) { y = x 2; } Simple if statement on one line.

if(x < 5) { y = x 2; }

Multi-line if statement

if(x < 5) { y = x 2; } else { y = x 3; }

If else statement.

if(x < 5) { if(x > 0) {y = x 2; } } else { y = x 3; }

Nested if statement with else.

See Also Loops , for

7.6 Plotting commandsLine and image plots are supported. These figures can be exported to jpeg images.

Plotting functions

Command Description

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plot Makes line plots.

plotxy Makes line plots, when data sets are sampled atdifferent position vectors.

polar Makes polar plots.

polar2 Makes polar plots, when data sets are sampled atdifferent position vectors.

polarimage Makes a 2D polar image plot.

histc Makes a histogram plot.

legend Makes a legend on a figure with line plots.

image Makes 2D image plots.

setplot Sets figure properties.

visualize Pass in simulation data to the visualizer.

vectorplot Makes vector plots.

Miscellaneous plotting functions

Command Description

selectfigure Selects a figure.

exportfigure Exports a figure.

closeall Closes all figure windows.

7.6.1 plot

Create line plots. All data sets must be sampled on the same position vector.

See plotxy for data sets that are sampled on different position vectors.

Syntax Description

out = plot(x,y); Creates a plot of y vs x, y and x are both 1D vectors withthe same length. The figure number is returned.

plot(x,y); x is a nx1 matrix.y is a nxm matrix.This will generate a graph with m lines. (y(1:n,1) vs x, y(1:n,2) vs x, etc)

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plot(x,y1,y2,y3); Creates a plot with 3 curves, x,y1, y2, y3 must be thesame length, returns the figure number.

plot(x,y, "x label", "y label","title");

Creates a plot of y vs x with axis labels and a title, returnsthe figure number.

plot(x,y, "x label", "y label","title", "options");

Creates a plot with desired options. Options can be be log10x, log10y, loglogplot points greyscalepolar (same as the polar script command)any comma separated list of the above, for example"log10x,greyscale"

Returns the figure number.

See Also Plotting commands , plotxy , legend , image , closeall , setplot ,exportfigure , visualize , vectorplot , polar

7.6.2 plotxy

Create line plots. In particular, this function is used when the data sets are sampled ondifferent position vectors.

Syntax Description

out = plotxy(x,y); Creates a plot of y vs x, y and x are both 1D vectors withthe same length. The figure number is returned.

plotxy(x1,y1,x2,y2,xn,yn); Creates a plot with multiple curves. The xn-yn pairs musthave the same length, but x1, x2, and xn can have differentstart-end values and resolutions. It returns the figurenumber.

plotxy(x1,y1,x2,y2, "x label","y label", "title");

Creates line plots with axis labels and a title, returns thefigure number.

See Also Plotting commands , plot , legend , image , closeall , setplot , exportfigure

, visualize , vectorplot

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7.6.3 polar

Create polar plots. All data sets must be sampled on the same position vector.

See polar2 for data sets that are sampled on different position vectors.

Syntax Description

out = polar(theta,rho) Creates a polar coordinate plot of the angle theta versusthe radius rho. theta is the angle from the x-axis to theradius vector specified in radians; rho is the length of theradius vector.

Theta and rho can be vectors of the same length, or if thelength of theta is n, then y can be a nxm matrix.

The figure number is returned.

polar(theta,rho1,rho2,rho3) Creates a plot with 3 curves, theta, rho1, rho2, rho3 mustbe the same length, returns the figure number.

polar(theta,rho,"x label", "ylabel", "title")


polar(theta,rho,"x label", "ylabel", "title", "options");



See Also Plotting commands , polar2 , legend , image , closeall , setplot ,exportfigure , polarimage , plot

7.6.4 polar2

Create polar plots. In particular, this function is used when the data sets are sampled ondifferent position vectors.

Syntax Description

out = polar2(theta,rho) Creates a polar coordinate plot of the angle theta versusthe radius rho. theta is the angle from the x-axis to the

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radius vector specified in radians; rho is the length of theradius vector.

Theta and rho can be vectors of the same length, or if thelength of theta is n, then y can be a nxm matrix.

The figure number is returned.

polar2(theta1,rho1,theta2,rho2)

Creates a plot with 2 curves. The two data sets can besampled on different theta vectors.

polar2(theta,rho,"x label", "ylabel", "title")


polar2(theta,rho,"x label", "ylabel", "title", "options");



See Also Plotting commands , polar , legend , image , closeall , setplot ,exportfigure , polarimage

7.6.5 polarimage

Create 2D polar image plots. This is typically used to plot far field data.

Syntax Description

polarimage(ux,uy,data); Creates a 2D image plot. If ux is of dimension N x 1, where ux goes from -1 to 1 uy is of dimension M x 1, where uy goes from -1 to 1 data must be of dimension N x M

out = image(ux,uy,data, "xlabel", "y label", "title");

Creates a 2D image plot with axis labelsOptionally returns the figure number.

image(ux,uy,data, "x label","y label", "title", "options");

Creates a 2D image plot with axis labels and options,options can be

logplot

See Also Plotting commands , plot , polar , image , closeall , setplot , exportfigure

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, visualize , Near to far field projections

7.6.6 histc

The script command create a histogram plot.

Syntax Description

out = histc(y); Creates a histogram plot of y.Returns the figure number.

histc(y,n); Creates a histogram plot of y, using n bins.Returns the figure number.

histc (y,n, "x label", "ylabel", "title");

Creates a histogram plot of y, using n bins, with axislabels and a title.Returns the figure number.

See Also Plotting commands , histogram , legend , plot , closeall , visualize

7.6.7 legend

Add a legend to a line plot.

Syntax Description

legend("legend1","legend2",...,"legendn");

Adds a legend to the selected figure.This function does not return any data.

See Also Plotting commands , legend , plot , closeall , visualize

7.6.8 image

Create 2D image plots.

Syntax Description

out = image(x,y,z); Creates a 2D image plot. If x is of dimension N x 1 y is of dimension M x 1 z must be of dimension N x M


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image(x,y,z, "x label", "ylabel", "title");

Creates a 2D image plot with axis labels, returns the figurenumber.

image(x,y,z, "x label", "ylabel", "title", "options");

Creates a 2D image plot with axis labels and options,options can be

logplot polar any comma separated list of the above

See Also Plotting commands , plot , closeall , setplot , exportfigure , visualize ,polarimage , vectorplot

7.6.9 visualize

Send data to the visualizer.

Syntax Description

visualize(R); Plots the dataset R in the Visualizer.

visualize("name", x,y,z, p1,"p1", p2,"p2", "a1",a1,"a2",a2);

Plots data on a spatial grid.name - Visualizer namex,y,z - spatial grid vectorsp1,"p1" - additional parameter vectors (vector, thenparameter name)."a1",a1 - data attributes (data name, then data matrix)

visualize("name", x,y,z, p1,"p1", p2,"p2", "a1",a1x,a1y,a1z);

Plot vector data "a1",a1x,a1y,a1z - data attributes (data name, then datamatrix X,Y,Z components)

visualize("name", p1,"p1", p2,"p2", "a1",a1x,a1y,a1z);

Plot data not attached to a spatial grid.

See Also Plotting commands , Datasets , exportfigure , image , plot , setplot ,closeall

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7.6.10 selectfigure

Selecting a figure will show the figure on screen (give it focus). A warning will be generatedif the figure does not exist.

Syntax Description

selectfigure; Selects the last figure that was created.This function does not return any data.

selectfigure(1); Selects figure 1.

See Also Plotting commands , exportfigure , image , plot , setplot , closeall

7.6.11 setplot

Set figure properties.

Syntax Description

?setplot; Creates a string which lists all figure properties for thefigure that is currently selected. Unless the setfigure()command was called, the most recently created plot willbe selected.

setplot("property", "propertyvalue");

Set the desired property of the currently selected figure toproperty value.

See Also Plotting commands , image , plot , visualize

7.6.12 exportfigure

Exports the current figure to a JPG image. If the file extension is not specified, ".jpg" will beused. The image size will be the same as the figure window size.

If a file is overwritten, a warning will be generated. If an export fails, a warning will begenerated.

Syntax Description

exportfigure("filename"); Exports the current figure to a JPG image with the name"filename".The exported image will have the same size as the current

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figure.

exportfigure("filename",xres,yres);

Exports the current figure to a JPG image with the name"filename".The exported image will have the specified resolution, xres,yres, in the x,y directions respectively.

See Also Plotting commands , selectfigure , image , plot , setplot , closeall ,visualize

7.6.13 closeall

Close all open figure windows.

Syntax Description

closeall; Close all open figure windows.This function does not return any data.

See Also Plotting commands , plot , image

7.6.14 vectorplot

The script command vectorplot creates a vector plot from a rectilinear dataset. Therectilinear dataset must be a vector, like the E field, and it must have no additionalparameters (i.e. if you have E vs. x,y.z.f and f has 2 or more values, then the commandfails). Generally, it is easier to use visualize(E) and then select the vector plot option.

Syntax Description

vectorplot(E); Creates a vector plot of the dataset

See Also Plotting commands , plotxy , legend , image , closeall , setplot ,exportfigure , plot

7.7 Adding ObjectsThe following commands can be used to add objects. Objects are always added to thelocation specified by the groupscope variable. Please note that not all the commands areavailable for all products. Please refer to the table at the bottom of the page for eachcommand to see which products it applies to.

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Simulation environment

Command Description

switchtolayout Closes the analysis window, deletes currentsimulation data and allows you to manipulatesimulation objects for a new simulation.

layoutmode Used to determine if the simulation file is open inlayout or in analysis mode.

groupscope Changes the group scope.

addgroup Adds a container group to the simulationenvironment.

addanalysisgroup Add an analysis group.

addobject Add an object from the object library.

addgridattribute Add a grid attribute object.

Structures

Command Description

addcircle Add a circle primitive.

addcustom Add a custom primitive.

addimport Add an import primitive.

addpyramid Add a pyramid primitive.

addpoly Add a polygon primitive

addrect Add a rectangle primitive.

addring Add a ring primitive.

addsphere Add a sphere primitive.

addsurface Add a surface primitive.

addstructuregroup Add a structure group.

Simulation region

Command Description

addfdtd Add an FDTD simulation area.

addeigenmode Adds a MODE simulation area.

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addpropagator Adds a propagator simulation object to the MODESolutions simulation environment.

addmesh Add a mesh override region.

adddevice Adds a DEVICE simulation area.

Sources

Command Description

adddipole Add a dipole source.

addgaussian Add a Gaussian source.

addplane Add a plane source.

addmode ; addmodesource Add a mode source.

addtfsf Add a TFSF source.

addimportedsource Add an imported source.

Monitors

Command Description

addindex Add an index monitor.

addeffectiveindex Add an effective index monitor.

addtime Add a time monitor.

addmovie Add a movie monitor.

addprofile Add a profile monitor.

addpower Add a power monitor.

addmodeexpansion Add a mode expansion monitor.

Create objects in Deck

Command Description

createbeam Creates a new Gaussian beam that is accessiblefrom the deck.

Simulation environment

Command Description

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switchtolayout Closes the analysis window, deletes currentsimulation data and allows you to manipulatesimulation objects for a new simulation.

switchtodesign Switches INTERCONNECT to design mode.

layoutmode Used to determine if the simulation file is open indesign (layout) or in analysis mode.

designmode Returns true if the simulation is currently in designmode.


Adding Elements

Command Description

addelement Adds an element from the INTERCONNECT elementlibrary.

Adding simulation objects

Command Description

adddope Add a constant doping region.

addcustomdoping Add a doping region with custom data.

adddiffusion Add a diffusion region.

addbulkgen Add a bulk generation region.

addimportdope Add an import primitive for a doping region.

addimportgen Add an import primitive for a generation region.

addcontact Add a contact to the electrical contacts table.

7.7.1 switchtolayout

Closes the analysis window and allows you to manipulate simulation objects for a newsimulation. If a simulation file is open in ANALYSIS mode, any commands to modifyobjects will return errors. You must switch to LAYOUT mode before modifying any objects.

Syntax Description

switchtolayout; Switches to LAYOUT mode.This function does not return any data.

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See AlsoAdding Objects , layoutmode

7.7.2 layoutmode

Used to determine if the simulation file is open in layout or in analysis mode.

Syntax Description

?layoutmode; Returns 1 if in layout mode, and 0 if in analysis mode.

See AlsoAdding Objects , switchtolayout , designmode

7.7.3 addgroup

Adds a container group to the simulation environment. This command is not available inINTERCONNECT.

Syntax Description

addgroup; Adds a container group to the simulation environment.This function does not return any data.

See AlsoAdding Objects , addtogroup , addstructuregroup , addanalysisgroup

7.7.4 addstructuregroup

Adds a structure group to the simulation environment. This command is not available inINTERCONNECT.

Syntax Description

addstructuregroup; Adds a structure group to the simulation environment.This function does not return any data.

See AlsoAdding Objects , addtogroup , adduserprop , addgroup , addanalysisgroup

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7.7.5 addanalysisgroup

Adds an analysis group to the simulation environment. This command is not available inINTERCONNECT.

Note: It is not currently possible to add user defined Analysis Parameters or Results from ascript.

Syntax Description

addanalysisgroup; Adds an analysis group to the simulation environment.This function does not return any data.

See AlsoAdding Objects , addtogroup , adduserprop , addgroup , addstructuregroup

7.7.6 addobject

Adds a object from the object library.

This command is available in FDTD and MODE Solutions.

Syntax Description

addobject("script_ID"); Adds an object from the object library.This function does not return any data.

?addobject; Returns names of objects in the library.

See AlsoAdding Objects , addtogroup , adduserprop

7.7.7 addcontact

Adds a new contact to the electrical contact table. This command is available in DEVICEonly.

Syntax Description

addcontact; Adds a new contact to the electrical contact table.This function does not return any data.

See AlsoAdding Objects

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7.7.8 addcircle

Adds a circle primitive to the simulation environment. This command is not available inINTERCONNECT.

Syntax Description

addcircle; Adds primitive to the simulation environment.This function does not return any data.


7.7.9 addcustom

Adds a custom primitive to the simulation environment. This command is available in FDTDand MODE.

Syntax Description

addcustom; Adds primitive to the simulation environment.This function does not return any data.


7.7.10 addimport

Adds an import primitive to the simulation environment. This command is available in FDTDand MODE.

Syntax Description

addimport; Adds primitive to the simulation environment.This function does not return any data.


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7.7.11 addpyramid

Adds a pyramid primitive to the simulation environment. This command is not available inINTERCONNECT.

Syntax Description

addpyramid; Adds primitive to the simulation environment.This function does not return any data.


7.7.12 addpoly

Adds a polygon primitive to the simulation environment. This command is not available inINTERCONNECT.

Syntax Description

addpoly; Adds primitive to the simulation environment.This function does not return any data.


7.7.13 addrect

Adds a rectangle primitive to the simulation environment.This command is not available inINTERCONNECT.

Syntax Description

addrect; Adds primitive to the simulation environment.This function does not return any data.


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7.7.14 addtriangle

Adds a 3 vertex, triangle shaped polygon primitive to the simulation environment. Thiscommand is not available in INTERCONNECT.

Syntax Description

addtriangle; Adds primitive to the simulation environment.This function does not return any data.

See AlsoAdding Objects , addpoly

7.7.15 addring

Adds a ring primitive to the simulation environment. This command is not available inINTERCONNECT.

Syntax Description

addring; Adds primitive to the simulation environment.This function does not return any data.


7.7.16 addsphere

Adds a sphere primitive to the simulation environment. This command is not available inINTERCONNECT.

Syntax Description

addsphere; Adds primitive to the simulation environment.This function does not return any data.


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7.7.17 addsurface

Adds a surface primitive to the simulation environment. This command is available in FDTDand MODE.

Syntax Description

addsurface; Adds primitive to the simulation environment.This function does not return any data.


7.7.18 addfdtd

Adds a FDTD simulation area to the simulation environment. This command is available inFDTD and MODE.

Syntax Description

addfdtd; Adds a simulation area to the simulation environment.This function does not return any data.


7.7.19 addeigenmode

Adds an eigenmode simulation object to the MODE Solutions simulation environment. Thiscommand is available in MODE only.

Syntax Description

addeigenmode; Add an eigenmode mode simulation region.


7.7.20 addpropagator

Adds a propagator simulation object to the MODE Solutions simulation environment. Thiscommand is available in MODE only.

Syntax Description

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addpropagator; Add a propagator mode simulation region.


7.7.21 addmesh

Adds a mesh override region to the simulation environment. This command is available inFDTD and MODE.

Syntax Description

addmesh; Adds a mesh override region to the simulation environment.This function does not return any data.


7.7.22 addmode

7.7.23 addmodesource

Adds a mode source to the simulation environment. This command is available in MODEonly.

Syntax Description

addmodesource; Adds source to the simulation environment.This function does not return any data.

See AlsoAdding Objects , addmode , updatesourcemode

7.7.24 adddipole

Adds a dipole source to the simulation environment. This command is available in FDTDand MODE.

Syntax Description

adddipole; Adds source to the simulation environment.This function does not return any data.

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7.7.25 addgaussian

Adds a gaussian source to the simulation environment. This command is available in FDTDand MODE.

Syntax Description

addgaussian; Adds source to the simulation environment.This function does not return any data.


7.7.26 addplane

Adds a plane wave source to the simulation environment. This command is available inFDTD and MODE.

Syntax Description

addplane; Adds source to the simulation environment.This function does not return any data.


7.7.27 addtfsf

Adds a Total Field Scattered Field (tfsf) source to the simulation environment. Thiscommand is available in FDTD and MODE.

Syntax Description

addtfsf; Adds source to the simulation environment.This function does not return any data.


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7.7.28 addimportedsource

Adds an imported source to the simulation environment. This command is available inFDTD only.

Syntax Description

addimportedsource; Adds source to the simulation environment.This function does not return any data.

See AlsoAdding Objects , asapimport , asapload , asapexport

7.7.29 addindex

Adds an index monitor to the simulation environment. This command is available in FDTDand MODE.

Syntax Description

addindex; Adds monitor to the simulation environment.This function does not return any data.


7.7.30 addtime

Adds a time monitor to the simulation environment. This command is available in FDTD andMODE.

Syntax Description

addtime; Adds monitor to the simulation environment.This function does not return any data.


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7.7.31 addmovie

Adds a movie monitor to the simulation environment. This command is available in FDTDand MODE.

Syntax Description

addmovie; Adds monitor to the simulation environment.This function does not return any data.


7.7.32 addprofile

Adds a profile monitor to the simulation environment. This command is available in FDTDand MODE.

Syntax Description

addprofile; Adds monitor to the simulation environment.This function does not return any data.


7.7.33 createbeam

Creates a new Gaussian beam that is accessible from the deck. This command is availablein MODE only.

Syntax Description

createbeam; Creates a Gaussian beam in the deck/global workspace.The Gaussian beam has the properties specified in theOverlap analysis->Beam tab of the analysis windowReturns the name of the Gaussian beam created, which isby default "gaussian#" (# being the total number ofGaussian beams existing in the current deck).


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7.7.34 adddevice

Adds a Device simulation region to the simulation environment. This command is onlyavailable in DEVICE.

Syntax Description

adddevice; Add a device simulation region.

See Also Adding Objects

7.7.35 adddope

Adds a region with constant doping to the simulation environment. This command is onlyavailable in DEVICE.

Syntax Description

adddope; Add a constant doping region.


7.7.36 adddiffusion

Adds a diffusion region to the simulation environment. This command is only available inDEVICE.

Syntax Description

adddiffusion; Add a diffusion region.


7.7.37 addimportdope

Adds a doping region to the simulation environment where the doping profile has been orwill be imported into DEVICE. This command is only available in DEVICE.

Syntax Description

addimportdope; Add an import primitive to define a doping region.

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7.7.38 addbulkgen

Adds a bulk generation region to the simulation environment. This command is onlyavailable in DEVICE.

Syntax Description

addbulkgen; Add a bulk generation region.


7.7.39 addimportgen

Adds a generation region to the simulation environment where the generation profile hasbeen imported into DEVICE. This command is only available in DEVICE.

Syntax Description

addimportgen; Add an import primitive to define a generation region.


7.7.40 addgridattribute

Adds a grid attribute object to the simulation environment. See the Reference Guide Attributes page for more information. This command is only available in FDTD.

Syntax Description

addgridattribute(type); Adds a grid attribute object to the simulation.type: Type of attribute to add. Options are "lcorientation", "permittivity rotation", or "matrix transform".

addgridattribute(type,value,x,y,z);

Adds a grid attribute with spatially varying data.type: Type of attribute to add. Options are "lcorientation", "permittivity rotation", or "matrix transform".value: the attribute value. Depending on the attributetype, the value may be a scalar number (i.e.concentration), a 3 element vector (i.e. orientation), 9element tensor, etc. The size of the value matrix should

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be Nx X Ny X Nz X M… , where Nx, Ny, Nz are the sizesof the position vectors, and M is the size of the attributevalue (scalar, vector, tensors, etc). x,y,z: Vectors that specify the position where theattribute values are specified.

ExampleThe following script is an excerpt from LCD_twist.lsf in the Twisted Nematic LCD

application example which defines a spatially varying liquid crystal.# define x/y/zx = 0;y = 0;z = linspace(0e-6,5e-6,100);

X = meshgrid3dx(x,y,z);Y = meshgrid3dy(x,y,z);Z = meshgrid3dz(x,y,z);n = matrix(length(x),length(y),length(z),3);

# define the orientation functionn(1:length(x),1:length(y),1:length(z),1) = cos(Z*pi*1e5);n(1:length(x),1:length(y),1:length(z),2) = sin(Z*pi*1e5);n(1:length(x),1:length(y),1:length(z),3) = Z;

# add LC import grid attributeaddgridattribute("lc orientation",n,x,y,z-2.5e-6); # center atz=0setnamed("LC attribute","nz",50); # set resolution


7.7.41 addelement

Adds an element from the INTERCONNECT element library to the simulation environment.This command is only available in INTERCONNECT.

Syntax Description

addelement("element"); Adds an element from the element library.If no element name is given, this command will add acompound element by default.

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7.7.42 addmodeexpansion

Adds a mode expansion monitor to the simulation environment. This command is availablein FDTD and MODE.

Syntax Description

addmodeexpansion; Adds a mode expansion monitor to the simulationenvironment.This function does not return any data.

See AlsoAdding Objects , Using Mode Expansion Monitors, setexpansion , removeexpansion

7.7.43 addeffectiveindex

Adds an effective index monitor to the simulation environment. This command is onlyavailable in MODE Solutions.

Syntax Description

addindex; Adds an effective index monitor to the simulationenvironment.This function does not return any data.


7.7.44 addchargemonitor

Adds a charge monitor to the simulation environment. This command is ONLY available inDEVICE.

Syntax Description

addchargemonitor; Adds a charge monitor to the simulation environment.

See AlsoAdding Objects , addpower, addfieldmonitor

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7.7.45 addfieldmonitor

Adds a charge monitor to the simulation environment. This command is ONLY available inDEVICE.

Syntax Description

addfieldmonitor; Adds a field monitor to the simulation environment.

See AlsoAdding Objects , addpower, addchargemonitor

7.8 Manipulating objectsPhysical structures, sources, monitors, and the simulation volume itself are consideredobjects. Objects generally have properties that can be modified.

Selecting and deleting objects

Command Description


deleteall Deletes all objects in the current group scope.

delete Deletes the selected objects.

selectall Selects all objects in the current group scope.

unselectall Unselect all objects.

select Selects objects with a given name in the currentgroup scope.

selectpartial Selects any objects where partialname can be foundin the name, in the current TAB.

shiftselect The same as select("name"); but does not unselectcurrently selected objects. Can be used to selectmultiple objects.

shiftselectpartial The same as selectpartial("partialname"); but doesnot unselect currently selected objects. Can be usedto select multiple objects.

Moving and copying objects

Command Description

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flipelement Flips an element in the schematic editor.

rotateelement Rotates and element in the schematic editor.

move Move an object.

copy Copy an object.

addtogroup Add an object/objects into a group.

Object properties

Command Description

adduserprop Add a user property to a structure group.

set Set a property of selected objects.

setnamed Set a property of any objects with a given name.

setcontact Set a property of an electrical contact.

setglobalmonitor Set global monitor properties.

setglobalsource Set global source properties.

setmodes Set mode labels.

setposition Set an element's vertical and horizontal positions.

setrectangle Set width and height of an element rectangle.

setactivesolver Set the specified solver as the active solver

runsetup Force group setup scripts to run.

get Get a property of selected objects.

getcontact Get a property of an electrical contact.

getnumber Get the number of selected objects.

getnamed Get a property of any objects with a given name.

getnamednumber Get the number of objects with a given name.

getglobalmonitor Get global monitor properties.

getglobalsource Get global source properties.

getposition Get current horizontal or vertical position of anelement.

getrectangle Get the width or height of an element rectangle.

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haveproperty Returns the number of selected objects with aparticular property.

importsurface Import surface data from a file. Only applies to importprimitives.

importsurface2 Import surface data from script variables. Onlyapplies to import primitives.

importnk Import n and k data from a file. Only applies to importprimitives.

importdoping Import data from Tecplot formatted file (text)

importnk2 Import n and k data from script variables. Onlyapplies to import primitives.

setsourcesignal Set a custom source time signal.

updatesourcemode Updates the mode for a mode source.

clearsourcedata Clears source data for an imported source, or theselected mode for a mode source.

setexpansion Associates a DFT monitor with a mode expansionmonitor.

removeexpansion Removes a DFT monitor from a mode expansionmonitor.

getname Returns the dataset name of the variable selected.

setname Sets the dataset name of the variable selected.

importdataset Imports an unstructured dataset named 'charge' to an'eh Density' grid attribute.

cleardataset Clear the dataset from any current grid attribute.

Controlling the view

Command Description

redraw Redraw graphics.

redrawoff Turn automatic redraw off.

redrawon Turn automatic redraw on.

redrawmode Get the current status of automatic redrawing; turn itoff or on

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setview Control how the graphics are drawn in the LayoutEditor

getview Get the current view control properties from theLayout Editor.

orbit A built in function to do an orbit of the perspectiveview with option of creating a movie.

framerate Measure graphics performance of your computer.

Undo and redo commands

Command Description

undo Undo last modify object command.

redo Redo command after an undo.

7.8.1 groupscope

Changes the group scope. Script commands that add or modify simulation object use thegroupscope property to know where to act within the object tree. For example, if you wantto delete everything within a particular group, set the groupscope to that group (i.e. ::model::my_group). If you want to delete all objects in the simulation, set the group scopethe root level (i.e. ::model).

Syntax Description

?groupscope; returns the current group scope

groupscope("group_name"); changes the group scope

See Also Manipulating objects , delete , selectall , select

7.8.2 deleteall

Deletes all objects in the current group scope.

Syntax Description

deleteall; Deletes all objects in the current group scope.This function does not return any data.

See Also Manipulating objects , groupscope

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7.8.3 delete

Deletes selected objects.

Syntax Description

delete; Deletes selected objects.This function does not return any data.


7.8.4 selectall

Selects all objects in the current group scope.

Syntax Description

selectall; Selects all objects in the current group scope.This function does not return any data.


7.8.5 unselectall

Unselect all objects and groups.

Syntax Description

unselectall; Unselects all objects and groups.This function does not return any data.

See Also Manipulating objects

7.8.6 select

Selects objects with a given name in the current group scope. A failed select command willhave the same result as the unselectall command.

Syntax Description

select("name"); Selects objects with the name "name" in the current groupscope.

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This function does not return any data.

select("group name::name"); Selects all objects with the name "name" located in thegroup named "group name". The group named "groupname" must be in the current group scope.

See Also Manipulating objects , groupscope , unselectall

7.8.7 selectpartial

Selects any objects with a given partial name, in the current TAB.

Syntax Description

selectpartial("partialname"); Selects any objects where "partialname" can be found inthe object name provided the object is not in a group. Toselect objects located in groups see the command below.This function does not return any data.

selectpartial("partialgroupname::partialname");

Selects any objects where "partialgroupname" can befound in the group name and "partialname" can be found inthe object name.


7.8.8 shiftselect

Same as select, but does not unselect other currently selected objects. Note that onlyobjects from the same "group" can be selected simultaneously.

Syntax Description

shiftselect("name"); The same as select("name"), but does not unselectcurrently selected objects. Can be used to select multipleobjects.This function does not return any data.

shiftselect("group name::name");

The same as select("groupname::name"), but does notunselect currently selected objects.


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7.8.9 shiftselectpartial

Same as selectpartial, but does not unselect other currently selected objects.

Syntax Description

shiftselectpartial("partialname");

The same as selectpartial("partialname"), but does notunselect currently selected objects. Can be used to selectmultiple objects. This function does not return any data.

shiftselectpartial("partialgroupname::partialname");

The same as selectpartial("partialgroupname::partialname"), but does not unselect currently selected objects. Can beused to select multiple objects.


7.8.10 flipelement

Flip element in the schematic editor. This command is only available in INTERCONNECT.

Syntax Description

flipelement("element"); Flips element in the schematic editor.

See Also Manipulating objects , rotateelement

7.8.11 rotateelement

Flip element in the schematic editor. This command is only available in INTERCONNECT.

Syntax Description

rotateelement("element"); Rotates element in the schematic editor.

See Also Manipulating objects , flipelement

7.8.12 move

Move selected objects.

Syntax Description

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move(dx); In 2D or 3D, move by dx

move(dx,dy); In 2D or 3D, move by dx and dy.This function does not return any data.

move(dx,dy,dz); In 3D, move by dx, dy, and dz.In 2D, dz will be ignored.

See Also Manipulating objects , copy , select

7.8.13 copy

Create a copy of the selected objects. The copied objects will typically be identical (samename, position, etc). For some objects that must have a unique name, '_1' will beappended to the name.

Syntax Description

copy; Copy the selected objects.

copy(dx); Same as copy; but with a specified move of dx.

copy(dx,dy); Same as copy; but with a specified move of dx, dy.

copy(dx,dy,dz); Same as copy; but with a specified move of dx, dy, dz.

See Also Manipulating objects , move , select , cp (copy files) , copytoclipboard

7.8.14 addtogroup

Add selected objects to a group. This command is not available in INTERCONNECT.

Syntax Description

addtogroup("group name"); Adds selected object(s) to a group. If a group with name"group name" already exists, then the objects are added tothe existing group. Otherwise, a group named "groupname" is created.This function does not return any data.

See AlsoManipulating objects , addgroup , addstructuregroup , addanalysisgroup ,adduserprop , runsetup

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7.8.15 adduserprop

Adds a user defined custom property to the Setup user defined Structure and Analysisgroups. This command is not available in INTERCONNECT.

Syntax Description

adduserprop("propertyname", type, value);

Adds a user property to a selected structure group. Thename is set to "property name". The type is an integerfrom 0 to 5. The corresponding variable types are0 number1 text2 length3 time 4 frequency5 materialThe value of the user property is set to value.

See AlsoManipulating objects , addstructuregroup , runsetup

7.8.16 set

Set a property of currently selected objects. This command will return an error in analysismode.

Syntax Description

?set; Returns a list of the properties of the selected object(s).

set("property",value); This will set the properties of a currently selected object,including pull-downs and check boxes. It cannot be usedto set the value of a selected object in a group. Value can be a number or string. This function does notreturn any data.

set("property",value,i); This form can be used to set the property of the ithselected object when multiple objects are selected. Itcannot be used to set the value of a selected object in agroup. The objects are ordered by their location in the object tree.The uppermost selected object is given the index 1, andthe index numbers increase as you go down the tree.

See Also

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Manipulating objects , get , setnamed , setmaterial , addmaterial ,haveproperty , runsetup , runanalysis

7.8.17 setnamed

Like the set command, except that the object name must be specified. This command willreturn an error in analysis mode.

Syntax Description

?setnamed("name"); Returns a list of the properties of the objects called name.

setnamed("name","property", value);

The same as set, but acts on objects with a specificname, instead of selected objects.

setnamed("name","property", value,i);

This form can be used to set the property of the ith namedobject when multiple objects have the same name. The objects are ordered by their location in the object tree.The uppermost selected object is given the index 1, andthe index numbers increase as you go down the tree.

setnamed("groupname::name", "property", value);

The same as set, but acts on objects within the groupnamed "groupname" that are named "name", instead ofselected objects.

setnamed("groupname::name", "property", value,i);

This form can be used to set the property of the ith objectwith the name "name" in the group "groupname" whenmultiple objects have the same name. The objects are ordered by their location in the object tree.The uppermost selected object is given the index 1, andthe index numbers increase as you go down the tree.

See Also Manipulating objects , set , get , getnamed , getnamednumber

7.8.18 setglobalmonitor

Set global monitor properties. This command will return an error in analysis mode. Thiscommand is available in FDTD and MODE.

Syntax Description

?setglobalmonitor; Returns a list of the global monitor properties

setglobalmonitor("property",value);

Set the global monitor property named "property" to avalue.This function does not return any data.

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See Also Manipulating objects , set , getglobalmonitor , setglobalsource , getglobalsource

7.8.19 setglobalsource

Set global source properties. This command will return an error in analysis mode. Thiscommand is available in FDTD and MODE.

Syntax Description

?setglobalsource; Returns a list of the global source properties

setglobalsource("property",value);

Set the global source property named "property" to a value.This function does not return any data.

See Also Manipulating objects , set , setglobalmonitor , getglobalmonitor ,getglobalsource

7.8.20 setmodes

Set mode labels. This command is only available in INTERCONNECT.

Syntax Description

setmodes (“TE,TM”); Set a list of comma separated mode labels that will sharethe same s-parameters. Orthogonal identifies areassociated to each mode from 1 to number of modes.

See Also Manipulating objects

7.8.21 setposition

Set horizontal and vertical positions of an element. This command is only available inINTERCONNECT.

Syntax Description

setposition("element",x,y); Set an element vertical and horizontal positions.

See Also Manipulating objects , getposition , setrectangle

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7.8.22 setrectangle

Set the width or height of an element rectangle. This command is only available inINTERCONNECT.

Syntax Description

setrectangle ("element",w,h); Sets the width (w) and height (h) of an element rectangle.

See Also Manipulating objects , getrectangle , setposition

7.8.23 getposition

Get the current horizontal or vertical position of an element. This command is only availablein INTERCONNECT.

Syntax Description

out=getposition("element",”x”);

Returns the current horizontal position of an element.

out=getposition("element",”y”);

Returns the current vertical position of an element.

See Also Manipulating objects , setposition , getrectangle

7.8.24 getrectangle

Get the width or height of an element rectangle. This command is only available inINTERCONNECT.

Syntax Description

out=getrectangle("element",”w”);

Returns the width of an element rectangle.

out=getrectangle("element",”h”);

Returns the height of an element rectangle.

See Also Manipulating objects , setrectangle , getposition

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7.8.25 get

Get a property from selected objects. The property names for the get command are thesame as the property names in the Edit dialogue box. For example, if you see a propertycalled "mesh accuracy", then you can use the command get("mesh accuracy"); to get thatproperty. It is possible to get numeric, string, drop down and checkbox properties.

Syntax Description

?get; Returns a list of the properties of the selected object(s).

out = get("property"); Gets the requested property value from the currentlyselected object. It cannot be used to get the property valueof a selected object in a group. If multiple objects are selected get("property") is the sameas get("property",i), where i is the number of the firstselected objects with the requested property. Out can be a matrix or a string, depending on the propertyrequested.

get("property",i); Gets the property of the ith selected object. Use this to acton a series of objects. It cannot be used to get the value ofa selected object in a group. The objects are ordered by their location in the object tree.The uppermost selected object is given the index 1, andthe index numbers increase as you go down the tree.

See Also Manipulating objects , getnumber , getnamed , getnamednumber , set ,haveproperty , runsetup

7.8.26 runsetup

Runsetup forces the setup scripts of structure and analysis groups to run.

In most cases, it is not necessary to use this function, as group setup scriptsautomatically re-run at the end of script, if the object has been modified. It is onlynecessary to use this function when you need to force the setup script to run before theend of your script file.

Syntax Description

runsetup; Forces setup scripts of groups to run.

See Also

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Manipulating objects , get , set , runanalysis

7.8.27 getnumber

Get the number of objects that are selected.

Syntax Description

out = getnumber; Returns the number of objects that are selected;

See Also Manipulating objects , get , getnamed , getnamednumber , set

7.8.28 getnamed

Get a property from objects with a given name.

If multiple objects are selected, and the values are different, the smallest value is returned. To be certain of the results, be sure that only one object is selected, or use the form ofgetnamed that allows a specific object to be selected.

Syntax Description

?getnamed("name"); Returns a list of the properties of the objects called name.

out = getnamed("name","property");

The same as get, but acts on objects with a specificname, instead of selected objects.

out=getnamed("name","property", i);

Gets the property of the ith named object. Use this to acton a series of objects.The objects are ordered by their location in the object tree.The uppermost selected object is given the index 1, andthe index numbers increase as you go down the tree.

out = getnamed("groupname::name","property");

The same as get, but acts on objects named "name"located in the group "groupname", instead of selectedobjects.

out = getnamed("groupname::name","property");

Gets the property of the ith object named "name" locatedin the group "groupname". Use this to act on a series ofobjects.The objects are ordered by their location in the object tree.The uppermost selected object is given the index 1, andthe index numbers increase as you go down the tree.

See Also

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Manipulating objects , get , getnumber , getnamednumber , set , setnamed

7.8.29 getnamednumber

Get the number of objects with a given name.

Syntax Description

out = getnamednumber( "name");

The same as getnumber, but acts on objects with aspecific name, instead of selected objects.

out = getnamednumber( "groupname::name");

The same as getnumber, but acts on all objects named"name" in the group "groupname", instead of selectedobjects.

See Also Manipulating objects , get , getnamed , getnumber , set , setnamed

7.8.30 getglobalmonitor


Syntax Description

?getglobalmonitor; Returns a list of the global monitor properties

?getglobalmonitor("property");

Returns the value of the requested property.

See Also Manipulating objects , get , setglobalmonitor , setglobalsource , getglobalsource

7.8.31 getglobalsource


Syntax Description

?getglobalsource; Returns a list of the global source properties

?getglobalsource("property"); Returns the value of the requested property.

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See Also Manipulating objects , get , setglobalmonitor , getglobalmonitor ,setglobalsource

7.8.32 getsolver

Returns the solver that is currently active. This command is only available in MODE.

Syntax Description

?getsolver; Returns the solver that is currently active.

7.8.33 haveproperty

Returns the number of selected objects with a particular property. This command is notavailable in INTERCONNECT.

Syntax Description

out = haveproperty("property");

Returns the number of selected objects with the specifiedproperty.

See Also Manipulating objects , get , set

7.8.34 importsurface

Import surface data. This command only applies to import primitives. The function returns 1if the data is successfully imported. Example script files showing how to use thesefunctions can be found in the Online Help. See the User Guide, Structures section. Thiscommand is available in FDTD and MODE.

Note: Non-uniform sampling of imported dataThe import object is primarily intended to load data that is sampled on a uniform mesh. Itis also capable of importing non-uniformly sampled data, but with some limitations. Themain limitation is that within the simulation file (.fsp or .lms) the import surface objectalways stores the data on a uniform mesh. When non-uniform data is imported, that datais interpolated onto a uniform mesh during at import time. The size of the newinterpolated uniform grid will be the greater of: a) the smallest grid size in the originaldata or, b) a grid size that results in 4 times the original number of sample points. Thesecond condition is intended to prevent the size of the interpolated surface data matrixfrom becoming extremely large in cases where the mesh is highly graded. If you areconcerned about the possibility of interpolation errors, the best option is to interpolate thedata onto a uniform mesh yourself, then import the uniformly sampled data into the

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simulation.It is worth remembering that the data stored within the import object will undergo asecond round of interpolation when it is interpolated onto the actual simulation meshcoordinates used by the actual simulation engine.

Clearly, the behavior of this object with respect to non-uniformly sampled data could beimproved. Rather than forcing all data to be stored on a uniform mesh, it could simplystore the original non-uniform data, then apply more sophisticated interpolation when thesimulation engine is generating the final simulation mesh. If such an improvement isimportant to you, please contact us at [email protected].

Syntax Description

out = importsurface(filename,upper_surface,file_units,x0,y0,z0,invertXY);

Import a surface from the file in the string filename ina three dimensional simulation. All arguments afterfilename are optional.

out = importsurface(filename,upper_surface,file_units,x0,y0,invertXY);

Import a surface from the file in the string filename ina two dimensional simulation. All arguments afterfilename are optional.

Parameter Default value Type Description

filename required string name of the file with surface datato import. May contain completepath to file, or path relative tocurrent working directory

upper_surface 1 number This optional argument should be1 to import the upper surface and0 to import the lower surface.

file_units "m" string The optional string argumentfile_units can be "m", "cm, "mm","microns" or "nm" to specify theunits in the file.

x0 0 number The optional arguments x0, y0 andz0 specify the data origin in theglobal coordinates of the GraphicalLayout Editor. For example, if youare importing a surface defined byan AFM that is on a slab of Si thatranges from 0 to 2 microns, you

Reference Guide240


should set z0 to 2 microns.

y0 0 number

z0 0 number

invertXY 0 number The optional argument invertXYcan be used to reverse how the xand y axes are read from the file.

See Also Manipulating objects , importsurface2

7.8.35 importsurface2

Import surface data from script variables. This command only applies to import primitives.The function returns 1 if the data is successfully imported. Example script files showinghow to use these functions can be found in the Online Help. See the User Guide,Structures section. This command is available in FDTD and MODE.

Note: Non-uniform sampling of imported dataThe import object is primarily intended to load data that is sampled on a uniform mesh. Itis also capable of importing non-uniformly sampled data, but with some limitations. Themain limitation is that within the simulation file (.fsp or .lms) the import surface objectalways stores the data on a uniform mesh. When non-uniform data is imported, that datais interpolated onto a uniform mesh during at import time. The size of the newinterpolated uniform grid will be the greater of: a) the smallest grid size in the originaldata or, b) a grid size that results in 4 times the original number of sample points. Thesecond condition is intended to prevent the size of the interpolated surface data matrixfrom becoming extremely large in cases where the mesh is highly graded. If you areconcerned about the possibility of interpolation errors, the best option is to interpolate thedata onto a uniform mesh yourself, then import the uniformly sampled data into thesimulation.It is worth remembering that the data stored within the import object will undergo asecond round of interpolation when it is interpolated onto the actual simulation meshcoordinates used by the actual simulation engine.


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Syntax Description

out = importsurface2(Z,x,y,upper_surface);

Import a surface from the variables Z, x and y in threedimensional simulations. The upper_surfaceargument is optional.


Z required matrix The two dimensional matrix thatdefines the surface.

x required matrix If Z is an NxM matrix, then xshould have dimension Nx1. Fortwo dimensional simulation, if Y isan Nx1 matrix then x should havedimension Nx1.

y required matrix If Z is an NxM matrix, then yshould have dimension Mx1.

upper_surface 1 number This optional argument should be1 to import the upper surface and0 to import the lower surface.

Y required matrix This argument should be an Nx1matrix that defines the surface fortwo dimensional simulations.

See Also Manipulating objects , importsurface

7.8.36 importnk

Import the refractive index (n and k) over an entire volume or surface from a file. Thiscommand only applies to import primitives. The function returns 1 if the data is successfullyimported. Example script files showing how to use these functions can be found in theOnline Help. See the User Guide, Structures section. This command is available in FDTDand MODE.

Note: Non-uniform sampling of imported dataThe import object is primarily intended to load data that is sampled on a uniform mesh. Itis also capable of importing non-uniformly sampled data, but with some limitations. Themain limitation is that within the simulation file (.fsp or .lms) the import surface objectalways stores the data on a uniform mesh. When non-uniform data is imported, that datais interpolated onto a uniform mesh during at import time. The size of the new

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interpolated uniform grid will be the greater of: a) the smallest grid size in the originaldata or, b) a grid size that results in 4 times the original number of sample points. Thesecond condition is intended to prevent the size of the interpolated surface data matrixfrom becoming extremely large in cases where the mesh is highly graded. If you areconcerned about the possibility of interpolation errors, the best option is to interpolate thedata onto a uniform mesh yourself, then import the uniformly sampled data into thesimulation.It is worth remembering that the data stored within the import object will undergo asecond round of interpolation when it is interpolated onto the actual simulation meshcoordinates used by the actual simulation engine.


Syntax Description

out = importnk(filename,file_units,x0,y0,z0,reverse_index_order);

Import n (and k) data from filename in threedimensional simulations. All arguments after thefilename are optional.

out = importnk(filename,file_units,x0,y0,reverse_index_order);

Import n and k data from filename in two dimensionalsimulations. All arguments after the filename areoptional.


filename required string name of the file with n (and k) datato import. May contain completepath to file, or path relative tocurrent working directory


x0 0 number The optional arguments x0, y0 andz0 specify the data origin in theglobal coordinates of the GraphicalLayout Editor. For example, if youdefined your volume with respect



to a particular point in space, forexample (0,0,-5) microns, thenyou should set z0 to -5 microns.

y0 0 number

z0 0 number

reverse_index_order 0 number The optional argument reverse_index_order can be set to1 to reverse how the indices areinterpreted in the file. It is best toverify the correct setting with agraphical import before using thescript command.

See Also Manipulating objects , importnk2

7.8.37 importnk2

Import the refractive index (n and k) over an entire volume or surface from script variables.This command only applies to import primitives. The function returns 1 if the data issuccessfully imported. Example script files showing how to use these functions can befound in the Online Help. See the User Guide, Structures section. This command isavailable in FDTD and MODE.


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Syntax Description

out = importnk2(n,x,y,z); Import n (and k) data from script variables in threedimensional simulations. All arguments are required.

out = importnk2(n,x,y); Import n (and k) data from script variables in twodimensional simulations. All arguments are required.


n required matrix The refractive index. This shouldbe an NxMxP matrix in threedimensions and an NxM matrix intwo dimensions. If it is complex-valued, then the imaginary part isinterpreted as k.

x required matrix If n is an NxMxP matrix, then xshould have dimension Nx1. Fortwo dimensional simulation, if n isan NxM matrix then x should havedimension Nx1. Values of x mustbe uniformly spaced.

y required matrix If n is an NxMxP matrix, then yshould have dimension Mx1. Fortwo dimensional simulation, if n isan NxM matrix then y should havedimension Mx1. Values of y mustbe uniformly spaced.

z 1 number If n is an NxMxP matrix, then zshould have dimension Px1.Values of z must be uniformlyspaced.

See Also Manipulating objects , importnk223 241



7.8.38 importnkobfuscated

This command is identical to importnk but makes it possible to import data from a file thathas been obfuscated. For details on how to obfuscate the data files, please see the OnlineHelp in the User Guide, Structures section. This command is available in FDTD Solutionsonly, for versions 8.6.3 and higher.



Syntax Description

out =importnkobfuscated(key,filename,file_units,x0,y0,z0,reverse_index_order);

Import n (and k) data from filename in three dimensionalsimulations. All arguments after the filename are optional.


key required string The key that is used to decryptthe obfuscated file.

Reference Guide246


filename required string name of the file with n (and k) datato import. May contain completepath to file, or path relative tocurrent working directory


x0 0 number The optional arguments x0, y0 andz0 specify the data origin in theglobal coordinates of the GraphicalLayout Editor. For example, if youdefined your volume with respectto a particular point in space, forexample (0,0,-5) microns, thenyou should set z0 to -5 microns.

y0 0 number

z0 0 number


See Also Manipulating objects , importnk

7.8.39 importbinary

Import binary data (1s and 0s) over an entire volume from a file. The object will be presentwherever the binary data is 1 and not when it is 0. This command only applies to importprimitives. The function returns 1 if the data is successfully imported. Example script filesshowing how to use these functions can be found in the Online Help. See the User Guide,Structures section. This command is available in FDTD and MODE.

Note: Non-uniform sampling of imported dataThe import object is primarily intended to load data that is sampled on a uniform mesh. Itis also capable of importing non-uniformly sampled data, but with some limitations. The

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main limitation is that within the simulation file (.fsp or .lms) the import surface objectalways stores the data on a uniform mesh. When non-uniform data is imported, that datais interpolated onto a uniform mesh during at import time. The size of the newinterpolated uniform grid will be the greater of: a) the smallest grid size in the originaldata or, b) a grid size that results in 4 times the original number of sample points. Thesecond condition is intended to prevent the size of the interpolated surface data matrixfrom becoming extremely large in cases where the mesh is highly graded. If you areconcerned about the possibility of interpolation errors, the best option is to interpolate thedata onto a uniform mesh yourself, then import the uniformly sampled data into thesimulation.It is worth remembering that the data stored within the import object will undergo asecond round of interpolation when it is interpolated onto the actual simulation meshcoordinates used by the actual simulation engine.


Syntax Description

out = importbinary(filename,file_units,x0,y0,z0,reverse_index_order);

Import binary data from filename in three dimensionalsimulations. All arguments after the filename areoptional.


filename required string name of the file with binary data toimport. May contain completepath to file, or path relative tocurrent working directory


x0 0 number The optional arguments x0, y0 andz0 specify the data origin in theglobal coordinates of the GraphicalLayout Editor. For example, if youdefined your volume with respect

Reference Guide248


to a particular point in space, forexample (0,0,-5) microns, thenyou should set z0 to -5 microns.

y0 0 number

z0 0 number


See Also Manipulating objects , importbinary2

7.8.40 importbinary2

Import binary data (1s and 0s) over an entire volume from script variables. The object will bepresent wherever the binary data is 1 and not when it is 0. This command only applies toimport primitives. The function returns 1 if the data is successfully imported. Example scriptfiles showing how to use these functions can be found in the Online Help. See the UserGuide, Structures section. This command is available in FDTD and MODE.


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Syntax Description

out = importbinary2(binary,x,y,z); Import binary data from script variables in threedimensional simulations. All arguments are required.


binary required matrix The binary data This should be anNxMxP matrix in three dimensionsand an NxM matrix in twodimensions. It should have onlyvalues of 0 or 1. If other values arepresent, all non-zero values will beinterpreted as 1.

x required matrix If n is an NxMxP matrix, then xshould have dimension Nx1. Fortwo dimensional simulation, if n isan NxM matrix then x should havedimension Nx1. Values of x mustbe uniformly spaced.

y required matrix If n is an NxMxP matrix, then yshould have dimension Mx1. Fortwo dimensional simulation, if n isan NxM matrix then y should havedimension Mx1. Values of y mustbe uniformly spaced.

z 1 number If n is an NxMxP matrix, then zshould have dimension Px1.Values of z must be uniformlyspaced.

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7.8.41 importbinaryobfuscated

This command is identical to importbinary but makes it possible to import data from a filethat has been obfuscated. For details on how to obfuscate the data files, please see theOnline Help in the User Guide, Structures section. This command is available in FDTDSolutions only, for versions 8.6.3 and higher.



Syntax Description

out =importbinaryobfuscated(key,filename,file_units,x0,y0,z0,reverse_index_order);

Import binary data from filename in three dimensional simulations.All arguments after the filename are optional.


key required string The key that is used to decryptthe obfuscated file.



filename required string name of the file with binary data toimport. May contain completepath to file, or path relative tocurrent working directory


x0 0 number The optional arguments x0, y0 andz0 specify the data origin in theglobal coordinates of the GraphicalLayout Editor. For example, if youdefined your volume with respectto a particular point in space, forexample (0,0,-5) microns, thenyou should set z0 to -5 microns.

y0 0 number

z0 0 number


See Also Manipulating objects , importbinary

7.8.42 updatesourcemode

Updates the mode profile of selected mode source. If there is no mode profile stored in thesource, then the mode with the highest effective index will be selected. If a mode isalready stored in the source, then the mode with the best overlap with the old mode will beselected. Note that the mode source must be selected before running this command. Thiscommand is available in FDTD and MODE.

Syntax Description

?updatesourcemode; Updates mode profile of the selected Mode source.

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Returns the fraction of electromagnetic fields thatoverlap between the old and the new mode

?updatesourcemode(mode_number);

Updates the mode source and selects the desiredmode number. For example, updatesourcemode(1);will calculate the fundamental mode. Please note thatmaking this call will force a recalculation of a mode,even if the same mode has previously been calculated.In addition, making this call will force the modeselection method to become "user select". Thisoptional argument was introduced in FDTD Solutions8.6.3 and MODE Solutions 6.5.3.

NOTE: Saving simulation files before using updatesourcemodeIf you have a script file which updates the simulation mesh, then you should use the savescript command before updating the source mode. This will ensure that the mesh hasbeen updated before the new mode is calculated.

NOTE: overlapThe fraction of electromagnetic fields that overlap between the two modes is given by theexpression below. It is also the fraction of power from mode2 that can propagate inmode1. For more information, please see overlap script command.

SdHESdHE

SdHESdHEoverlap

*22

*11

*12

*21

Re

1Re

See AlsoManipulating objects , addmode , clearsourcedata , clearmodedata , getresult

, overlap, expand , seteigensolver , geteigensolver

7.8.43 setsourcesignal

Sets a custom source time signal.

This is an advanced source setting for users wanting a custom source time signal. For thevast majority of simulations, a custom time signal is not required. If this function is notused, the time signal will be automatically generated. This command is available in FDTDand MODE.

For an example script file which uses this script command, see Online User Guide->Sources->Custom time signal.

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Syntax Description

setsourcesignal("name", t,amplitude, phase);

Sets the time domain signal of source named "name". t,amplitude, and phase are 1D vectors with the same length.

setsourcesignal("name", t,amplitude, phase, fcentre,bandwidth);

Allows you to specify the precise center frequency andbandwidth that will be used for all simulations. These valuesare used for materials fits, calculating the mesh, and sourcelimits.If fcentre and bandwidth are not specified, they will beautomatically estimated from the time signal.

See Alsosourcepower

7.8.44 updatemodes

Updates the mode profile(s) of selected mode expansion monitor If there are no modeprofiles stored in the mode expansion monitor, then the mode with the highest effectiveindex will be selected. If mode profiles are already stored in the mode expansion monitor,then the modes with the best overlap with the old modes will be selected. Note that themode expansion monitor must be selected before running this command. This command isavailable in FDTD and MODE.

Syntax Description

updatemodes; Updates mode profile of the selected mode expansionmonitor. Returns 1 if the update was successful and -1 if not.

updatemodes(mode_number); Updates the mode expansion monitor and selects thedesired mode numbers. For example,updatesourcemode(1:10); will calculate the 10 modeswith the highest refractive index. Please note thatmaking this call will force a recalculation of a modes,even if the same modes have previously beencalculated. In addition, making this call will force themode selection method to become "user select". Thisoptional argument was introduced in FDTD Solutions8.6.3 and MODE Solutions 6.5.3.

NOTE: Saving simulation files before using updatesourcemodeIf you have a script file which updates the simulation mesh, then you should use the save

Reference Guide254


script command before updating the source mode. This will ensure that the mesh hasbeen updated before the new mode is calculated.

NOTE: overlapThe fraction of electromagnetic fields that overlap between the two modes is given by theexpression below. It is also the fraction of power from mode2 that can propagate inmode1. For more information, please see overlap script command.

SdHESdHE

SdHESdHEoverlap

*22

*11

*12

*21

Re

1Re


, overlap, expand , seteigensolver , geteigensolver

7.8.45 clearsourcedata

Clears source data for an imported source, or the selected mode for a mode source. Thiscommand is available in FDTD and MODE.

Syntax Description

clearsourcedata; Clears source data for the selected source.

ExampleClear source data from an imported source. This will make the file much smaller, whichcan be convenient when emailing simulation files.

select("source3");clearsourcedata;

See Alsoupdatesourcemode , asapimport , asapload , asapexport , clearmodedata ,getresult , overlap, expand , seteigensolver , geteigensolver

7.8.46 clearmodedata

Clears mode data for a mode expansion monitor This command is available in FDTD andMODE, as of versions 8.6.3 and 6.5.3 respectively. This is mainly useful to reduce filesizes when saving.

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Syntax Description

clearmodedata; Clears mode data for the selected mode expansion mnoitor.

See Alsoupdatesourcemode , asapimport , asapload , asapexport , clearsourcedata ,getresult , overlap, expand , seteigensolver , geteigensolver

7.8.47 seteigensolver

Mode sources and mode expansion monitors in FDTD and MODE have embeddedeigensolvers. This script command makes it possible to set the properties of thateigensolver without using the GUI.

Changing any values of the embedded eigensolver with this command will automaticallyinvalidate any existing mode data. This means that new updates based on overlapcalculations with previous modes will fail after using this command. Therefore please callthis command before making any calls to updatesourcemode or updatemodes.

Syntax Description

?seteigensolver; Returns a list of the properties of the embeddedeigensolver

seteigensolver("property",value);

This will set the eigensolver properties of the currentlyselected objects.Value can be a number or string. This function does notreturn any data.

ExampleChange the radius of curvature for a mode expansion calculation, and calculate the first 10modes which can be subsequently used for mode expansion.

select("mode_expansion");seteigensolver("bent waveguide",true);seteigensolver("bend radius",10e-6);updatemodes(1:10);


, overlap, expand , seteigensolver , geteigensolver , updatemodes ,

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updatesourcemode

7.8.48 geteigensolver

Mode sources and mode expansion monitors in FDTD and MODE have embeddedeigensolvers. This script command makes it possible to get the properties of thateigensolver without using the GUI.

Syntax Description

?geteigensolver; Returns a list of the properties of the embeddedeigensolver

geteigensolver("property"); This will get the eigensolver properties of the currentlyselected objects. The returned value may be a number or astring, depending on the property.

ExampleChange the radius of curvature for a mode expansion calculation, and calculate the first 10modes which can be subsequently used for mode expansion.

select("mode_expansion");?geteigensolver("bent waveguide");


, overlap, expand , seteigensolver , geteigensolver , updatemodes ,updatesourcemode

7.8.49 redraw

Force the graphical viewports of the CAD to update. The viewports update automatically bydefault, so this command is only required after using the redrawoff command. Thiscommand is not available in INTERCONNECT.

Syntax Description

redraw; Redraws graphics.This function does not return any data.

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See Also Manipulating objects , redrawon , redrawoff , redrawmode

7.8.50 redrawoff

Disable automatic updating of the graphical viewports in the CAD. This can greatlyincrease the speed of scripts that add large numbers of objects. This command is notavailable in INTERCONNECT.

Syntax Description

redrawoff; Prevents redrawing of graphics.This function does not return any data.Cannot use this command in group setup scripts sinceredrawing is automatically turned off.

See Also Manipulating objects , redrawon , redraw , redrawmode

7.8.51 redrawon

Enable automatic updating of the graphical viewports in the CAD. Automatic updating isthe default behavior, so this command is only required after using the redrawoff command.This command is not available in INTERCONNECT.

Syntax Description

redrawon; Turns redrawing back on.This function does not return any data.

See Also Manipulating objects , redraw , redrawoff , redrawmode

7.8.52 redrawmode

This command can be used to determine the current status of automatic redrawing. It canalso be used to set the current status of automatic redrawing. The graphics will be redrawnafter any script command that may change the properties of a graphical object. Thiscommand is not available in INTERCONNECT.

Syntax Description

out = redrawmode; The value of out indicates if automatic redrawing is off or onout=1: automatic redrawing is onout=0: automatic redrawing is off

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out = redrawmode(in); Set the automatic redrawing off or on. To turn it on, usein=1. To turn it off, use in=0. The value of out is set afterexecuting the command so that out=in once this commandhas been executed.

See Also Manipulating objects , redraw , redrawoff

7.8.53 setview

This command allows the viewing properties of the Layout Editor to be modified. Thiscommand is not available in INTERCONNECT.

Syntax Description

outstring = setview; Returns a list of the view properties that can be set. Thecommand?setview;

will returnextent, zoom, theta, phi

setview("property"); Sets the default value for any of the view properties. Forexample,setview("extent");

is the same as pressing the graphical extent button.

setview("property",value); Sets the values to of any property for viewing.

The following table describes the properties that can be set

Property Description

extent Control the view extent. In this case, value should be a2x1, 4x1 or 6x1 matrix representing the view range min x,max x, min y, max y, min z and max z respectively.

zoom Controls the relative zoom of the perspective viewcompared to the default level. To zoom in by a factor of 2 inthe perspective view, use setview("zoom",2);

theta Controls the polar angle of the perspective view, indegrees.

phi Controls the azimuthal angle of the perspective view, indegrees.

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See Also Manipulating objects , getview , orbit , redraw

7.8.54 getview

This command allows the viewing properties of the Layout Editor to be retrieved. Thiscommand is not available in INTERCONNECT.

Syntax Description

outstring = getview; Returns a list of the view properties that can be set. Thecommand?getview;

will returnextent, zoom, theta, phi

out = getview("property"); Returns the current value of any of the view properties. Forexample,zoom_level = getview("zoom");

will return the current zoom setting of the perspective viewrelative to the default level.

The properties that can be obtained with getview are described in setview .

See Also Manipulating objects , setview , orbit , redraw

7.8.55 orbit

This command performs an elliptical viewing orbit of the structure in the perspective view.Note that the commands setview , getview and redraw make it possible to createany type of orbit you would like in your own script file. This command is not available inINTERCONNECT.

Syntax Description

orbit; Performs an orbit of the current perspective view.

orbit(zoom_factor); Performs an orbit with the specified minimum zoomfactor. By default the zoom factor is 1.5.

orbit(zoom_factor, frame_rate); Performs an orbit with the specified frame ratespecified in frames per second. The default frame rateis 15.

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orbit(zoom_factor, frame_rate,"filename");

The orbit will be streamed to the mpeg file filename forlater viewing.

See Also Manipulating objects , setview , getview , framerate

7.8.56 framerate

Orbits the perspective view and returns the framerate. This can be useful for estimating yourgraphics performance. If comparing the performance of two computers, be sure to useexactly the same simulation file. This command is available in FDTD only.

Syntax Description

fr = framerate(num_frames,zoom);

num_frames - Number of frames to drawzoom - Zoom factor used in perspective viewfr - number of frames / wall time required to completeorbit.

See Also Manipulating objects , setview , getview , orbit

7.8.57 undo

Undo the last command that modified any objects, you can undo the last 5 commands.

Syntax Description

undo; Undo last modify object command.This function does not return any data.

See Also Manipulating objects , redo

7.8.58 redo

Redo a command after a previous undo.

Syntax Description

redo; Redo command after previous undo.This function does not return any data.

See Also

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Manipulating objects , undo

7.8.59 addport

Add a port to a compound/script element. (Note that this command does not apply forprimitive elements.) This command is only available in INTERCONNECT.

Syntax Description

addport("element", "port","type", "data");

Adds a new port to the element with the specifiedproperties.Returns the name of the port that is created.

Property Defaultvalue

Type Description

element required string Name of the element to add aport to.

port required string Name of the port to add. Thenamed will be modified if thereis already a port of the samename.

type required string The type of port to add. Theoptions are: Bidirectional,Input, Output, Analyzer Input

data required string The type of data for the port.The options are: Variant,Optical Signal, ElectricalSignal, Digital Signal

Manipulating objects , removeport

7.8.60 removeport

Remove a port from a compound/script element. (Note that this command does not applyfor primitive elements.) This command is only available in INTERCONNECT.

Syntax Description

removeport("element","port");

Removes "port" from "element".Returns 1 if the port is successfully removed, 0 otherwise.

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Manipulating objects , addport

7.8.61 connect

Connects one element to another via the specified ports. This command is only available inINTERCONNECT.

Syntax Description

connect("element1", "port1","element2", "port2");

Connects "port1" of "element1" to "element2" or "port2".

Manipulating objects , disconnect

7.8.62 disconnect

Disconnect one element to another via the specified ports. This command is only availablein INTERCONNECT.

Syntax Description

connect("element1", "port1","element2", "port2");

Deletes the connection between "port1" of "element1" and"port2" of "element2".

Manipulating objects , connect

7.8.63 setexpansion

Associates a DFT monitor with a mode expansion monitor. This command is available inFDTD and MODE.

Syntax Description

?setexpansion; List all monitors under the "Monitors for expansion" list forthe selected mode expansion monitor.

setexpansion("name","dft_monitor");

Adds the "dft_monitor" to the "Monitors for expansion" listof the selected mode expansion monitor, with the specifiedname.

addmodeexpansion , removeexpansion , Using Mode Expansion Monitors

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7.8.64 removeexpansion

Removes a DFT monitor from a mode expansion monitor. This command is available inFDTD and MODE.

Syntax Description

removeexpansion("name"); Removes the DFT monitor with the specified name from the"Monitors for expansion" list of the selected modeexpansion monitor.

addmodeexpansion , setexpansion , Using Mode Expansion Monitors

7.8.65 setactivesolver

Set the specified solver as the active solver. For example, this can be used to togglebetween the Eigenmode solver and Propagator simulations in MODE Solutions. Thiscommand is available only in MODE.

Syntax Description

?setactivesolver; Lists all the possible solver choices

setactivesolver('solver_name');

Set the solver with the specified name as the active solver.

7.8.66 getname

The script command getname is used to get the name of a datset.

Syntax Description

?getname(a); Returns the name of the dataset of the variable a.

?a.getname; Returns the name of the dataset of the variable a.

See Alsosetname

7.8.67 setname

The script command setname is used to set the name of a datset.

Syntax Description

a.setname("test"); Returns the name of the dataset of the variable a.

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See Alsogetname

7.8.68 importdataset

This command can import charge density to a selected 'eh density' grid attribute. A filecontains an unstructured dataset called 'charge' with scaler attributes 'n' and 'p' can beexported from DEVICE, for example Mach_Zehnder. The unstructured dataset 'charge' inthis file can be imported to the 'eh Density' grid attribute in FDTD, MODE or DEVICE, byGUI or this command. This command is NOT available in INTERCONNECT.

Syntax Description

importdataset("device_data.mat")

Imports the unstructured dataset 'charge' in the file fromthe current working directory.

importdataset(charge) Implements 'charge' from the file that is already importedby matlabload

Property Description

device_data.mat A Matlab formatted file, that contains data exported fromDEVICE

charge Name of an unstructured data set

See Also Manipulating objects , cleardataset

7.8.69 cleardataset

This command clears the dataset from any current eh Density grid attribute. This is onlyuseful for keeping file size small.This command is ONLY available in MODE and DEVICE.

Syntax Description

cleardataset; clears the dataset from any current eh Density gridattribute.

See Also Manipulating objects , importdataset

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7.9 Running simulationsMoving between tabs

Command Description

switchtolayout Closes the analysis window and allows you tomanipulate simulation objects for a new simulation.

layoutmode Used to determine if the simulation file is open inlayout or in analysis mode.

Running Simulations

Command Description

run Launch the simulation. (Options available)

runparallel Launch the simulation in parallel mode.

addjob Add a simulation to the job queue.

runjobs Run all simulations in the job queue.

clearjobs Remove all simulations from the job queue.

runsweep Runs a parameter sweep or optimization task

Command Description

run Launch the simulation. (Options available)

runsweep Runs a parameter sweep or optimization task

7.9.1 runparallel

Launch the simulation in parallel mode. Equivalent to run and run(3). When the simulationfinishes, all simulation data will be saved to the current file. This command has beendeprecated. Use run.

Syntax Description

runparallel; Launch the simulation in parallel mode as defined in theresource manager. This function does not return any data.

See Also run, runanalysis

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7.9.2 addjob

Adds a simulation file to the job manager queue. This command is not available inINTERCONNECT.

Syntax Description

addjob(filename); Add the simulation file "filename" to the job managerqueue.

See Also run, runsweep , runjobs , clearjobs , currentfilename

7.9.3 runjobs

Run all simulations in the job manager queue. The script execution will be paused whilethe jobs run, then resume when all of the simulations have complete successfully. If errorsoccur, the script will not proceed. This command is not available in INTERCONNECT.

Syntax Description

runjobs; Run jobs in the Job queue. Use the computer resourcesand parallel settings that are specified in the ResourceManager.

runjobs(option); option=0: run jobs in single process mode using only thelocal computer.option=1: run jobs using the computer resources andparallel settings that are specified in the ResourceManager. (default)

See Also run, runsweep , addjob , clearjobs , save , load

7.9.4 clearjobs

Remove all jobs from the job manager queue. This command is not available inINTERCONNECT.

Syntax Description

clearjobs; Remove all jobs from the Job queue.

See Also run, addjob , runjobs

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7.9.5 runsweep

Runs a parameter sweep or optimization task.

Syntax Description

runsweep; Runs all sweeps and optimization tasks.

runsweep("taskname"); Runs only the sweep or optimization named taskname.

See Also run, getsweepdata , addjob , runjobs

7.10 Measurement and optimization dataThe following commands are used to access data from simulation objects.

Most raw data is recorded in multi-dimensional form. For example, monitors in FDTD andMODE Solutions typically return data in 4D matrices. The first three dimensions of thematrix correspond to the spatial dimensions X, Y, Z. The 4th dimension corresponds to thefrequency or time dimension, depending on the type of monitor. For example, suppose youhave a FDTD Solutions simulation with a frequency monitor in the XY plane that records 20frequency points. Assuming the monitor spans 100 mesh points in the x direction and 55mesh points in the y direction, the size of the Ex field component data matrix will be100x55x1x20. Notice that the 3rd dimension (corresponding to Z) has a size of 1, sincethe monitor only recorded data at one Z position.

Command Description

getresult Get results from simulation objects.

getdata Get raw data from simulation objects.

getelectric Get raw |E|2 data matrix from monitor

getmagnetic Get raw |H|2 data matrix from monitor

runanalysis Runs the analysis script in analysis objects

clearanalysis Clears d-card data obtained by running analysisscripts.

havedata Used to see if there is any available data storedwithin an object.

haveresult Used to see if there are any available results withinan object.

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read and write data to file Read and write data to a file.

copydcard Creates a copy of a d-card.

cleardcard Clears a d-card.

Parameter sweep,optimization, and yield analysis data is saved with the simulation file andis not cleared when switching the current simulation to layout mode. These results can beaccessed with the following commands:

Command Description

getsweepdata Gets raw data from parameter sweeps,optimizations, and yield analysis.

getsweepresult Gets results from parameter sweeps andoptimizations.

havesweepdata Used to check if parameter sweep and optimizationshave data.

havesweepresult Used to check if parameter sweep and optimizationshave results.

loadsweep Loads previously generated sweep result

savesweep Saves the generated sweep result

issweep Checks if the simulation is in sweep mode.

7.10.1 getsweepdata

Gets raw data from a parameter sweep, optimization, or yield analysis. In most cases, it ismore convenient to a complete dataset with getsweepresult, rather than getting individualdata elements with getsweepdata.

Syntax Description

?getsweepdata; Returns names of all sweep, optimization, and yieldanalysis objects.

?getsweepdata("sweep_name");

Returns all the names of the available data which is storedin the sweep, optimization, or yield analysis object.

out = getsweepdata("sweep_name", "data");

Returns parameter sweep, optimization, or yield analysisdata.

The following data can be obtained from an optimization:

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fomTrend - Figure of merit as a function of generationfomHistory - Figure of merit history (for each generationthere will be generation size number)bestFom - Best figure of merit obtained during sweepbestParameter - Parameter which corresponds tobestFomparamHistory - Parameter history

For a parameter sweep and yield analysis, this commandreturns both parameters and results.

See Alsogetdata , runsweep , havesweepdata , savedata , getsweepresult , savesweep

, loadsweep

7.10.2 getsweepresult

Get parameter sweep or optimization results in the form of a dataset.

Syntax Description

?getsweepresult; Returns names of all sweep or optimization objects withavailable results.

?getsweepresult("sweep_name");

Returns names of the available results from the sweep oroptimization task.

out = getsweepresult("sweep_name", "result");

Returns parameter sweep or optimization dataset.

See AlsoDataset introduction , runsweep , havesweepresult , getresult , savedata ,getsweepdata , savesweep , loadsweep

7.10.3 getdata

Get data from the simulation. Remember to run the simulation before using getdata.

Syntax Description

?getdata; Returns names of all objects with data.

?getdata("monitor") Returns list of of results within the simulation object.

?getdata( "monitor","result");

Returns list of of data within the simulation object result.

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out = getdata( "monitor","result", "dataname");

Gets the simulation data.

See AlsoMeasurements , havedata , getsweepdata

7.10.4 getresult

Get results from simulation objects. Results will be returned as datasets.

Syntax Description

?getresult("monitor_name"); Returns the names of all the results for the monitor. All thedataset and scalar matrix results will be returned in thiscase.

R = getresult("monitor_name","T");

Returns the result T from the monitor. T is a dataset.

See AlsoMeasurements , haveresult , Dataset introduction , "." operator , visualize ,getdata , rectilineardataset , matrixdataset , getattribute , addattribute ,splitstring

7.10.5 runanalysis

Runs the analysis script in analysis objects.

Note: Scripts that already have data are not re-run; to re-run a script, first clear data usingclearanalysis.

Syntax Description

runanalysis; Runs the analysis scripts in all analysis objects in thesimulation file.This function does not return any data.

runanalysis("group name"); Runs the analysis script in the analysis object named"group name".This function does not return any data.

See Also

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run, getdata , getresult , havedata , clearanalysis , runsetup

7.10.6 havedata

Used to see a simulation object (such as a monitor) has any data. This command is verysimilar to haveresult, but is intended to be used with the getdata command, rather thangetresult. This command is not available in INTERCONNECT.

Syntax Description

havedata; Returns 1 if any simulation objects have raw data, and 0 ifnone have any raw data.

havedata("name"); Returns 1 if "name" has raw data, and 0 if it does not haveany raw data.

havedata("name","data"); Returns 1 if "name" has the raw data named "data", and 0if it does not have that data.

See AlsoMeasurements , getdata , haveresult , getresult , copydcard , cleardcard ,workspace , havesweepdata

Available in

FDTD SolutionsMODE SolutionsINTERCONNECTDEVICE

YesYesNoYes

7.10.7 haveresult

Used to see a simulation object (such as a monitor) has any results.

Note: This command is very similar to havedata, but is intended to be used with thegetresult command, rather than getdata.

Syntax Description

haveresult; Returns 1 if any simulation objects currently have anyresults.

haveresult("name"); Returns 1 if "name" has any results, and 0 if it does not.

haveresult("name","data"); Returns 1 if the "name" has a result named "data", and 0 ifit does not.

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See AlsoMeasurements , getresult , havedata , getdata , copydcard , cleardcard ,workspace , havesweepdata

7.10.8 havesweepdata

Used to check if parameter sweep and optimizations have data. Similar to havedata, but forsweeps and optimization tasks.

Syntax Description

havesweepdata; Returns 1 if any sweeps or optimizations have data.Returns 0 if data is not available.

havesweepdata("name"); Returns 1 if the specified sweep or optimization has data.

havesweepdata("name","data");

Returns 1 if the sweep or optimization "name" has thespecified data.

See AlsoMeasurements , runsweep , getsweepdata , getdata , havedata

7.10.9 havesweepresult

Used to check if parameter sweep and optimizations have results. Similar to haveresult, butused for checking if sweeps and optimization tasks have available results.

Syntax Description

havesweepresult; Returns 1 if any sweeps or optimizations have results.Returns 0 if data is not available.

havesweepresult("name"); Returns 1 if the specified sweep or optimization hasresults.

havesweepresult("name","data");

Returns 1 if the sweep or optimization "name" has thespecified result.

See AlsoMeasurements , runsweep , getsweepresult , getresult , haveresult

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7.10.10 copydcard

Will create a global copy of any d-card currently in memory. This command is available inFDTD and MODE.

Syntax Description

copydcard( "name"); Will create a global copy of any d-card currently in memorycalled "name". By default, the new name will be "::global_name".This function does not return any data.

copydcard( "name","newname");

Will create a global copy of any d-card currently in memorycalled "name". The new name will be "::newname".

See AlsoMeasurements , havedata , cleardcard

Available in

FDTD SolutionsMODE SolutionsINTERCONNECTDEVICE

YesYesNoNo

7.10.11 clearanalysis

Clears analysis object results. This data is also cleared by switching from Analysis Modeto Layout Mode. This command is not available in INTERCONNECT.

Note: The analysis object results are calculated with the runanalysis command.

Syntax Description

clearanalysis; Clears analysis object results. This function does not return any data.

clearanalysis( "name1","name2", ...);

Clears data from specific analysis objects.

See AlsoMeasurements , switchtolayout , getdata , runanalysis , havedata

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7.10.12 cleardcard

Clears global d-cards. Only global d-cards are cleared. Local d-cards are associated withthe current simulation and can only be cleared by switching from Analysis Mode to LayoutMode. This command is available in FDTD and MODE.

Syntax Description

cleardcard; Clears all the global d-cards. This function does not return any data.

cleardcard( "name1","name2", ...);

Clears any number of specified d-cards.

See AlsoMeasurements , havedata , copydcard

7.10.13 getelectric

Returns the sum of the amplitude squares for all electric field components, i.e. it returns |

Ex|2+|Ey|2+|Ez|2. This command is available in FDTD and MODE.

Syntax Description

out = getelectric( "monitorname");

Returns |Ex|2+|Ey|2+|Ez|2 from the monitor.

getelectric( "monitorname",option);

The optional argument, option, can have a value of 1 or 2. Ifit is 2, the data is unfolded where possible according to thesymmetry or anti-symmetric boundaries if it comes from amonitor that intersect such a boundary at x min, y min or zmin. The default value of option is 2.

See AlsoMeasurements , getdata , getmagnetic , cwnorm, nonorm

7.10.14 getmagnetic

Returns the sum of the amplitude squares for all magnetic field components, i.e. it returns |

Hx|2+|Hy|2+|Hz|2. This command is available in FDTD and MODE.

Syntax Description

out = getmagnetic( "monitorname");

Returns |Hx|2+|Hy|2+|Hz|2 from the monitor.

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getmagnetic( "monitorname", option);

The optional argument, option, can have a value of 1 or 2. Ifit is 2, the data is unfolded where possible according to thesymmetry or anti-symmetric boundaries if it comes from amonitor that intersect such a boundary at x min, y min or zmin. The default value of option is 2.

See Also Measurements , getdata , getelectric , cwnorm, nonorm

7.10.15 Read and write data to files

Please see the following section for file I/O commands.System level commands: File input and output

7.10.16 loadsweep

The script command loads the sweep object with the previously generated sweep result.

Syntax Description

loadsweep; Loads previously generated sweep result to all the sweepobjects in simulation.

loadsweep("name"); Loads previously generated sweep result to the specifiedsweep objects in simulation.

See AlsoMeasurements , getdata , runsweep , havesweepdata , savedata ,getsweepresult , savesweep

7.10.17 savesweep

The script command saves the sweep object results.

Syntax Description

savesweep; Saves the sweep result of all sweep objects in simulation.

savesweep("name"); Saves the sweep result of the specified sweep object.

See AlsoMeasurements , getdata , runsweep , havesweepdata , savedata ,getsweepresult , loadsweep

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7.11 Material databaseThe following commands are used to add or copy materials in the material database, aswell as to set any material property and verify the resulting complex index of a givenmaterial at any frequency. (The permittivity can be easily obtained by squaring the index.)Please see the chapter on the material database to understand the usage of thesecommands.This section is not relevant for INTERCONNECT.

Command Description

addmaterial Adds a new material into the material database.

copymaterial Copies an existing material in the material database

setmaterial Sets any property of an existing material in thematerial database.

getmaterial Returns properties of a material in the materialdatabase.

getindex Returns the complex index of a material.

getfdtdindex Returns the material index as it will be in an actualFDTD simulation.

getmodeindex Returns the material index as it will be in an actualMODE simulation.

getnumericalpermittivity An advanced function that returns permittivity, takinginto account the effect of finite size of dt in an FDTDsimulation.

7.11.1 addmaterial

Adds a new material to the material database. This command is not available inINTERCONNECT.

Syntax Description

?addmaterial; Displays all types of materials that can be added into thematerial database.

out = addmaterial("materialtype");

Adds a new material and returns the name of the newmaterial. The argument "materialtype" is has to matchcorrect string exactly.

See Also

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Material database , setmaterial , getindex , getfdtdindex

7.11.2 copymaterial

Makes a copy of a material in the material database. This command is not available inINTERCONNECT.

Syntax Description

out = copymaterial("materialname");

Creates a copy of the material "materialname". The newname is returned.

See AlsoMaterial database , setmaterial , getindex , getfdtdindex

7.11.3 setmaterial

Modifies properties of a material in the material database. This command is not available inINTERCONNECT.

Syntax Description

?setmaterial("materialname");

Displays the property names of the specified material thatcan be modified.

setmaterial( "materialname","propertyname", newvalue);

Sets the property named "propertyname" of the materialwith the name "materialname" to newvalue. The argumentnewvalue can be a number or a string. The arguments"propertyname" and "materialname" have to match correctstring exactly. For example, setmaterial("Si","Mesh order",4);will set the property "mesh order" of the materials "Si" to4.

See AlsoMaterial database , addmaterial , getmaterial , getindex , getfdtdindex

7.11.4 getmaterial

Returns properties of a material in the material database. This command is not available inINTERCONNECT.

Syntax Description

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?getmaterial( "materialname");

Displays the property names of the specified material thatcan be modified.

out = getmaterial( "materialname","propertyname");

Returns the property named "propertyname" of the materialwith the name "materialname". The returned variable iseither a matrix or a string, depending on the property in thequery.

See AlsoMaterial database , addmaterial , setmaterial , getindex , getfdtdindex

7.11.5 getindex

Returns the complex index of any material that is in the material database. The index atthe specified frequency is interpolated from the neighboring frequencies where the indexdata is available. This command is available in FDTD and MODE.

Syntax Description

out = getindex( "materialname", f);

Returns the complex index of the material with the givenname. The index is returned for the specified frequency f. Frequency f is in Hz.

getindex( "materialname", f,component);

Optional argument component can be 1, 2 or 3 to specifythe x, y or z component for anisotropic materials. Thedefault is 1.

See AlsoMaterial database , getfdtdindex , getmodeindex , addmaterial , setmaterial

7.11.6 getfdtdindex

This function returns the material index of a material in the database as it will be used in anactual FDTD simulation.

Many materials (such as Sampled materials) have properties that depend on frequency.Using getfdtdindex, you can specify frequency range, and the fitting routine will find a bestfit of the material data over that range. The index evaluated at the specified f is thenreturned. Note that the fit result depends on the fit parameters, Max coefficients andTolerance set for the material, thus getfdtdindex result depends on those parameters aswell.


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Syntax Description

out = getfdtdindex( "materialname", f, fmin,fmax);

Returns the complex index of the material with the givenname. The index is returned for the specified frequency f.Similar to getindex, but you also specify fmin and fmax,the span of frequency of the FDTD simulation. Allfrequency units are in Hz.

getfdtdindex("materialname",f,fmin, fmax, component);


See AlsoMaterial database , getindex , getmodeindex , addmaterial , setmaterial

7.11.7 getmodeindex

This function returns the material index of a material in the database as it will be used in anactual MODE simulation.

Many materials (such as Sampled Materials) have properties that depend on frequency.Using getmodeindex, you can obtain the refractive index as a function of the specifiedfrequency, f, as it will be used in MODE calculations. Note that when multi-coefficientmodels are used, the fit result depends on the fit parameters, Max coefficients andTolerance set for the material. This command is available in FDTD and MODE.

Syntax Description

out = getmodeindex( "materialname", f);

Returns the complex index of the material with the givenname. The index is returned for the specified frequency f.This result is identical to getindex unless the optionalarguments fitsampled and fitanalytic are used. Allfrequency units are in Hz.

getmodeindex("materialname", f,component);


getmodeindex("materialname", f,component, fitsampled,fitanalytic, fmin, fmax);

Optional arguments to specify if Sampled Materials orAnalytic Materials should be fitted using Lumerical's multi-coefficient model (MCM), which is commonly used inFDTD simulations. If either of these options are set to 1(true) then you must supply a minimum and maximum

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frequency for fitting. The MCM is typically used in MODESolutions for

Sampled Materials when calculating waveguidedispersion, and forAnalytic Materials only for the purpose of using preciselythe same materials in both FDTD and MODEsimulations.

The default values are 0 (false) for fitsampled andfitanalytic.

See AlsoMaterial database , getindex , getfdtdindex , addmaterial , setmaterial

7.11.8 getnumericalpermittivity

This advanced function returns the permittivity of a material in the database as it will beused in an actual FDTD simulation, including the effects of a finite time step, dt. In FDTD,the relationship between the displacement field, D, and the electric field, E, is given by

EdtD r ,0

In the limit where dt tends to zero, we have

20 ,lim ndtrdt

where n( ) is the refractive index returned by the script function getfdtdindex, or shown inthe Materials Explorer. If you set dt to zero when calling this function, it will return exactlythe same result as the square of getfdtdindex.

The name of the function is a reminder that it returns the numerical permittivity, ie, the ratioof D and E, which is different from the refractive index, ie the ratio of the speed of light in avacuum to the phase velocity of light in the medium. To understand the relationshipbetween the them, we must consider the full, numerical dispersion relation between andk which is given by

2222

2sin

1

2sin

1

2sin

1

2sin

1,

dzk

dz

dyk

dy

dxk

dx

dt

cdtdt zyx

r

In the limit where dt, dx, dt and dz tend to zero, it is easy to show that we have theexpected result

)()0,( n

ck

dt

ck

r

The spatial FDTD mesh and time step are generally chosen to obtain a desired level ofsimulation accuracy, essentially by ensuring that the arguments of the sine functions are

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sufficiently small that sin(x)~x and that the simulation is stable. For some materials, it maybe desired to further reduce the value of the time step, dt, without modifying the spatialFDTD mesh, in order to obtain a higher level of accuracy for

r( ,dt). This script function

makes it possible to calculate, in advance, the value of dt required to obtain the desiredaccuracy for the permittivity.


Syntax Description

out =getnumericalpermittivity( "materialname", f, fmin,fmax, dt);

Returns the complex permittivity of the material with thegiven name. The permittivity is returned for the specifiedfrequency f. This is similar to getfdtdindex except for theadditional parameter dt. All frequency units are in Hz.

getnumericalpermittivity("materialname", f,fmin,fmax, dt, component);


See AlsoMaterial database , getindex , addmaterial , setmaterial , getfdtdindex

7.12 GDSIIThe following commands can be used to import and export GDSII files.

Command Description

gdsopen Opens a GDSII file for writing.

gdsclose Closes a GDSII file for writing.

gdsbegincell Starts a new cell in a GDSII file.

gdsendcell Finishes a cell in a GDSII file.

gdsaddpoly Adds a polygon element to a GDSII file stream.

gdsaddcirlce Adds an approximation of a circle to a GDSII filestream.

gdsaddrect Adds a rectangle element to a GDSII file stream.

gdsaddref Adds a reference to another cell to the current cell inthe GDSII file stream.

gdsimport Imports a cell from a .gds file into the layoutenvironment.

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7.12.1 gdsopen

This function creates a new .gds file and returns a file handle that can be used with theother GdsWriter functions to write the file. The default database units are in 0.1nm and theuser units are microns. The GDSII export function works as a group of commands, shownbelow as an example. For more information, please see Userguide - GDSII - Import andexport.

Syntax Description

f = gdsopen("filename","userUnit", "dataBaseUnit")

Opens a .gds file in the current directory, specifies the sizeof user units and size of the GDSII file units. f is a filehandle to open the GDSII file.

Parameter Type Description

filename string name of the GDSII file to export, may also contain afile path.

userUnit number size of user units in GDSII file units.

databaseUnit number size of the GDSII file units in meters.

See Alsogdsclose , gdsbegincell , gdsendcell , gdsaddpoly , gdsimport

7.12.2 gdsclose

This function closes a GDSII file for writing. Before calling this command, a .gds file has tobe previously opened, see gdsopen .

Syntax Description

gdsclose("filename") closes a .gds file in the current working directory.


filename string name of the GDSII file to export, may also contain afile path.

See Alsogdsopen , gdsbegincell , gdsendcell , gdsaddpoly , gdsimport

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7.12.3 gdsbegincell

This function creates a cell in a GDSII file. All GDS elements (polygons, boxes, references,array references, etc) must be placed inside a cell, so this function must be called beforeadding any elements. When finished adding elements, gdsendcell can be called to finish

the cell. Cells cannot be nested, so after calling gdsbegincell, a new cell cannot be

called again until the first called cell has been closed. Although the GDSII file is a flat list ofcells, cells can reference other cells, thus creating a nested hierarchy. See gdsaddreffor more details. A GDS "cell" exists as a "structure group" when imported to FDTD, see gdsimport for more details.

Syntax Description

gdsbegincell(f, "cellname") Creates a new cell in a GDSII file.


f string a file handle that was previously opened with gdsopen.

cellname string name of the cell.

Note: Just to clarify, a GDS cell is different from a Cell Array in FDTD.

See Alsogdsopen , gdsclose , gdsendcell , gdsaddpoly , gdsaddref , gdsimport ,cell

7.12.4 gdsendcell

This function finishes a cell in a GDSII file. This function ends the current cell in the GDSIIfile stream. The command gdsbegincell has to be called before closing a cell.

Syntax Description

gdsendcell(f) Finishes the previously created cell in a GDSII file.



See Alsogdsopen , gdsclose , gdsbegincell , gdsaddpoly , gdsimport

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7.12.5 gdsaddpoly

This function adds a polygon element to a GDSII file stream. Polygons are also known asboundary elements in GDS terminology. This command can be called only if a cell hasbeen created.

Syntax Description

gdsaddpoly(f, layer,[vertices])

Adds a polygon element on a layer with vertices.



layer number layer number for this structure.

vertices vector vertices of the polygon, in a 1D vector. They aregrouped in XY pairs e.g., {x1,y1,x2,y2,...xn,yn}. Thevalues are in meters. The first and last values shouldnot be the same, the polygon will be automaticallyclosed.

See Alsogdsopen , gdsclose , gdsbegincell , gdsendcell , gdsaddcircle , gdsaddref, gdsimport

7.12.6 gdsaddcircle

This function adds an approximation of a circle to a GDSII file stream. GDSII files do notsupport circles, so this is just a convenient function to create a polygon representation of acircle. Polygons can only be added in a GDSII cell, so this command can be called only ifa cell has been created.

Syntax Description

gdsaddcircle(f, layer, x, y, r,n)

Adds an approximation of a circle on a layer with x-, y-coordinates, radius and number of polygon sides.



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x number x-coordinate of the center position in meters.

y number y-coordinate of the center position in meters.

r number radius of the circle in meters.

n number number of sides to use in the polygon approximation.It is 64 by default.

See Alsogdsopen , gdsclose , gdsbegincell , gdsendcell , gdsaddpoly , gdsaddref ,gdsimport

7.12.7 gdsaddrect

This function adds a rectangle element to a GDSII file stream. This is just a convenientfunction to create a polygon for the case of a rectangle. Other element type for rectangle(such as, box) is not supported at this moment. Polygons can only be added in a GDSIIcell, so this command can be called only if a cell has been created.

Syntax Description

gdsaddrect(f, layer, x, y,width, height)

Adds a rectangle element on a layer with x-, y-coordinates,width and height.




x number x-coordinate of the center position in meters.

y number y-coordinate of the center position in meters.

width number width of the rectangle in meters.

height number height of the rectangle in meters.

See Alsogdsopen , gdsclose , gdsbegincell , gdsendcell , gdsaddpoly , gdsaddref ,gdsimport

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Reference Guide286


7.12.8 gdsaddref

This function adds a reference to another cell to the current cell in the GDSII file stream.This function replicates the referenced cell (has to be previously opened and finished) to thecurrent cell, to create a nested hierarchy. The layer numbers of the replicated structuresfollow the referenced cell. References can only be added in a GDSII cell, so this commandcan be called only if a current cell has been created. In addition, the cell to be replicatedhas to exist before it is referenced.

Syntax Description

gdsaddref(f, "cellname", dx,dy)

Adds a reference to another cell ("cellname") to the currentcell, with a specified move of dx and dy.


f string a file handle that was previously opened withgdsopen.

cellname string name of the referenced cell.

dx number x-movement of the replicated cell in the current cell.

dy number y-movement of the replicated cell in the current cell.

See Alsogdsopen , gdsclose , gdsbegincell , gdsendcell , gdsaddpoly , gdsaddcircle

, gdsaddrect , gdsimport

7.12.9 gdsimport

This command imports a cell from a .gds file into the layout environment. This is equivalentto performing a GDSII import through the FILE->IMPORT menu. See the Reference Guide- Layout editor chapter , Reference Guide - GDSII Import and Userguide - GDSII -Import and export for more information.

This command is NOT available in INTERCONNECT.

Syntax Description

n = gdsimport("filename","cellname", layer);

Imports the specified layer from the specified cell in thespecified file into the current simulation environment. Theobjects created will have their material set to an objectdefined dielectric. In 3D, the 2D geometric data will be

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extruded to default values in the Z dimension. The optionalreturned value, n, is the number of objects that wereimported from the gds file.

n = gdsimport("filename","cellname", layer,"material");

Same as the above command, but the material of theimported object will be set to the value specified.

n = gdsimport("filename","cellname", layer,"material", zmin, zmax);

This form of the command is only allowed in 3D layouts.The behavior is the same as the above command, but thestructures will be extruded in the Z dimension to thespecified z min and z max values


filename string name of the GDSII file to import. It can contain acomplete path to file, or path relative to the currentworking directory.

cellname string name of the cell to import from the GDSII file.

layer number orstring

the layer number from the GDSII file to import. If onlyelements matching a certain data type are desired,this can be specified by using a string of the form:

"6:2"where the desired layer is 6 and the desired datatype is 2.

material string a valid name of a material in your current layoutenvironment. Partial names of materials can bematched starting at the beginning of the string. Forexample, "Al (3" would match "Al (300nm)".

zmin number the minimum z value for extruding 2D GDSII data into3D objects

zmax number the maximum z value for extruding 2D GDSII datainto 3D objects

Example:This command imports "cell_1", on the first layer in the GDS_export.gds file, with a

specified material, z min and z max assigned. For more examples, please visit ReferenceGuide - GDSII Import , and Userguide - GDSII - Import and export for associated files.gdsimport("GDS_export.gds", "cell_1", 1, "Ag (Silver) - CRC", 0,1e-6);

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See AlsoSystem level , setnamed , fileexists , gdsopen

7.13 User defined GUIsCustom GUIs can be created with the following commands.

Command Description

message Creates a message window that displays some text.

newwizard Used to create a new user defined wizard.

newwizardpage This creates a page for the wizard.

wizardwidget Adds a new widget to the current wizard window.

runwizard Runs the wizard and returns a value indicating whichbutton was pressed.

wizardgetdata Returns data entered into a specific widget.

killwizard This closes the wizard window.

wizardoption Sets some options for wizard widgets and labels.

fileopendialog Calls the standard windows file open dialog.

filesavedialog Calls the standard windows file save dialog.

Typically, a wizard will be created with the following steps1. Open a new wizard with newwizard2. Add a new wizard page with newwizardpage3. Add widgets to the wizard page with wizardwidget4. Call runwizard to run the wizard5. Use wizardgetdata to obtain values entered into widgets by the user6. Depending on the values returned by runwizard , the wizard can be closed with

killwizard , or a new wizard page is started with newwizardpage .

7.13.1 message

Creates a message window that displays some text. The user must hit Enter, or click theOK button to continue.

Syntax Description

message("text"); Creates a window that displays text.

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This function does not return any data.

See AlsoUser defined GUI , newwizard

7.13.2 newwizard

Used to create a new user defined wizard. Opens a new wizard window.

Syntax Description

newwizard( w, h, "title"); w and h (width and height) are specified in pixels. Theminimum values for w and h are 200. title is the wizard window title.

See AlsoUser defined GUI , message

7.13.3 newwizardpage

This creates a page for the wizard and should be done before adding any widgets.

Syntax Description

newwizardpage( "label1"); Creates a button with the label "label1". Typically, this willbe "Done" or "OK".

newwizardpage( "label1","label2");

Creates two buttons with labels "label1" and "label2".These will typically be "Next" and "Back" or "Done" and"Back".

See AlsoUser defined GUI , newwizardpage

7.13.4 wizardwidget

Adds a new widget to the current wizard window. This command should only be done aftercreating a new wizard page with the command newwizard.

Syntax Description

wizardwidget( "type","name");

type can be"number" for a numeric input field"string" for a alphanumeric field"checkbox" for a checkbox

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"menu" for a pulldown menu field"label" to add a string label (wizardgetdata does notreturn information for labels)

name is a string used to give the input field, checkbox,menu item or label a name.

wizardwidget( "type", "label",defaultValue);

defaultValue provides a default value for numeric inputs,checkboxes, menu items or strings.

wizardwidget( "type", "label","choices", defaultValue);

If the "type" of widget is a "menu", then the menu choicesmust be provided. These choices should be separated bythe character "|". For example, to create a pulldown widgetwith the name "simulation type" and 3 choices"TE","TM","3D", with the default choice "3D", thecommand iswizardwidget("menu","simulation type","TE|TM|3D",3);


7.13.5 wizarddata

This command will cause the wizard window to wait until the user selects OK or Cancel. Itthen returns value data from the matrix in a N+1 length matrix, where N is the number ofwidgets (excluding labels) in the current wizard page.

This function is only available in MODE Solutions.

Syntax Description

out = wizarddata; The values of out areout(1) = 0, 1 or -1. 0 means the user pressed Cancel, 1means the user pressed the first button (typically "OK"or "Next") and -1 means the user pressed the secondbutton (typically "Back")out(2:N+1) gives the numeric values that the userentered for each input field when out(1) is 1. Note thatcheck boxes return 1 if checked and 0 if unchecked.Menu items return a number between 1 and M where Mis the number of choices in the menu. If out(1) is 0 or -1,all the values out(2:N+1) are zero.

See Also User defined GUI , newwizard

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7.13.6 runwizard

Runs the wizard and returns a value indicating which button was pressed.

Syntax Description

out = runwizard; Returns either 0, +1 or -1.0 means the user pressed Cancel, 1 means the userpressed the first button (created by calling newwizardpage)and -1 means the user pressed the second button (createdby calling newwizardpage).


7.13.7 wizardgetdata

Returns data entered into a specific widget.

This function is only available in MODE Solutions.

Syntax Description

out = wizardgetdata(N); Returns the value that the user entered into the Nth widget.Out will be a number or a string, depending on the type ofwidget.

See Also User defined GUI , newwizardpage

7.13.8 killwizard

This closes the wizard window. It should only be called after a wizard window has beencreated with the newwizard command.

Syntax Description

killwizard; This closes the wizard window.


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7.13.9 wizardoption

Sets some options for wizard widgets and labels.

Syntax Description

wizardoption ("optionname",setting);

The options are"fontsize" sets the font size to any value between 8 and40"fieldwidth" sets the width of each widget field to anyvalue between 20 and the full width of the wizard window."fieldheight" sets the height of each field to any valuebetween 8 and the full height of the wizard window."margin", sets size of the left margin to any valuebetween 0 and full width of the wizard window.

See AlsoUser defined GUI , newwizard

7.13.10 fileopendialog

Calls the standard windows file open dialog.

Syntax Description

out = fileopendialog; Brings up the open file dialog box and returns the path thatthe user selects.

out = fileopendialog(".ext"); Brings up the open file dialog box, displaying only files withthe extension .ext. Returns the path of the file that the userselects.

See Also User defined GUIs , filesavedialog

7.13.11 filesavedialog

Calls the standard windows file save dialog.

Syntax Description

out = filesavedialog; Brings up the save file dialog box and returns the path thatthe user selects.

out = filesavedialog(".ext"); Brings up the save file dialog box, displaying only files withthe extension .ext. Returns the path of the file that the user

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selects.

See Also User defined GUIs , fileopendialog

7.14 Creating your own script commandsRunning a script file from the script promptYou can run any script file simply by typing the name of the file (without the .lsf extension).For example, if you create the file create_array.lsf, you can run this file from the commandprompt, or another script file, with the commandcreate_array;

The current working directory is always in the Lumerical script path, and is the mostcommon location for your script files. You can add additional locations to the path withthe addpath script function. The following location (within the installation directory) is

also always in the path, making it a convenient place to put script functions that may beneeded my all users of the computer. It will be necessary to have admin access to savefiles in this location.C:\Program Files\Lumerical\FDTD\scripts (Windows)

/usr/local/lumerical/scripts (Linux)

Note: Saving script files with the same name as built in script functionsIt is generally not recommended to create script files that have the same name as thestandard script functions. In such cases, where there is a conflict between a script file andstandard script function, the script file will run. In other words, this allows you to overridethe behavior of a standard script function. This can be helpful, but it can also lead toconfusing behavior when done unintentionally.

Calling one script file from anotherOnce you start creating complex scripts, it may be convenient to split them up into anumber of simpler scripts that call one another. If you have multiple scripts in the samedirectory then they can call each other just as you would use any other scriptingcommand.

Note: All script files use a common variable space. As a consequence, variables defined in thescripts are global, and the script files have access to all variables defined in the simulationproject file. This can lead to problems when two script files use the same variable names.For example, script_1.lsf (defined below) will print the value 10 to the command line

since script_2.lsf modified the variable i.script_1.lsfi=1;

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script_2;?i;

script_2.lsffor(i=1:10) { # do something}

Formatting tipsMultiple commands are allowed on a single line.Blank lines, space and tabs will be ignored. Therefore you can format your script filesany way you choose. Each command must be terminated with a semicolon. On any line, all characters after a # symbol are ignored.

Finally, you can not define a variable or assign values to a variable that has the same nameas one of the script commands. For example, the following linessum = matrix(1,2);angle = acos(pi/2);

are not valid statements since 'sum' and 'angle' are script functions.

Index 295


Index' 156

- 150

! 154, 155

!= 152

" 155

# 157

% 133

& 153

* 150

/ 150

: 132

? 157

[] 132

151

| 154

~ 155

+ 150

< 153

<= 152

= 132

== 151

> 153

>= 152

abs 164

absolute 164

access 137

acos 163

addanalysisgroup 210

addbulkgen 220

addcircle 211

addcustom 211

adddevice 219

adddiffusion 219

adddipole 215

addeigenmode 214

addfdtd 214

addgaussian 216

addgridattribute 220

addgroup 209

addimage 211

addimportdope 219

addimportedsource 217

addimportgen 220

addindex 217

addition 150

addjob 266

addmaterial 276, 277

addmesh 215

addmode 215

addmodesource 215

addmovie 218

addobject 210

addpath 119

addplane 216

addpoly 212

addprofile 218

addpropagator 214

addpyramid 212

addrect 212

addring 213

addsphere 213

addstructuregroup 209

addsurface 214

addtfsf 216

addtime 217

addtogroup 230

addtriangle 213

adduserprop 231

almostequal 151

analysis group 70

analysis tools 81

and 153

angle 165

arccos 163

arcsin 162

Reference Guide296


arctan 163

array 132, 137, 138

asap 123, 124

asapexport 123

asapimport 124

asapload 124

asin 162

assign 137

assignment 132

atan 163

atan2 163

break 120

c 138

CAD layout 29

cd 115

ceil 188

centroid 184

changing CAD layout 39

clear 136

clearanalysis 273

cleardcard 274

clearjobs 266

clearmodedata 254

clearsourcedata 254

clock 116

closeall 205

comment 157

comparison 151

conj 164

conjugate 164

copy 115, 230

copydcard 273

cos 162

cosine 162

cp 115

createbeam 218

cross 168

ctranspose 175

currentfilename 117

czt 183

data export 83

date 116

del 113, 114

delete 227

deleteall 226

detail 60

dir 114

division 150

dot 168

double quote 155

edit 31

eig 169

eigenvalue 169

eigenvector 169

else 197

endl 157

eps0 138

equal 132

equal to 151

equation interpreter 76

escape 120

eval 176

exit 116

exp 166

exponential 166

exportfigure 204

feval 176

fft 178

fftk 181

fftw 180

filebasename 117

filedirectory 118

fileexists 117

fileextension 118

fileopendialog 292

filesavedialog 292

find 174

findpeaks 174

Index 297


findstring 177

finite 191

flip 170

flipelement 229

floor 188

for 196

format 121

framerate 260

gaussian 190

gds 286

gdsii 60, 286

geometry 59

get 235

getcommands 118

getdata 269

geteigensolver 256

getelectric 274

getfdtdindex 278

getglobalmonitor 237

getglobalsource 237

getindex 278

getmagnetic 274

getmaterial 277

getmodeindex 279

getnamed 236

getnamednumber 237

getnumber 236

getnumericalpermittivity 280

getpath 119

getsolver 238

getsweepdata 268

getview 259

graphics graphical rendering 60

greater than 153

greater than or equal to 152

groupscope 226

havedata 271

haveproperty 238

if 197

imag 164

image 202

imaginary 164

import 60, 286

import object 58

importbinary 246, 250

importbinary2 248

importnk 241

importnk2 243

importnkobfuscated 245

importsurface 238

importsurface2 240

inpoly 185

integrate 173

integrate2 173

interp 171

interpolate 171, 172

interptri 172

inverse 182

invfft 182

killwizard 291

layoutmode 209

legend 202

length 166

less than 153

less than or equal to 152

linecross 188

lineintersect 187

linspace 133

ln 165

load 113, 121

loaddata 121

location 59

log 165

log10 165

loop 196

ls 114

main 30

main title bar 29

Reference Guide298


material 59

material database 42

matlab 83, 125

matlabget 127

matlabput 127

matlabsave 124

matrix 133, 138, 169

max 168

mesh 54

mesh refinement region 65

meshgrid3dx 135

meshgrid3dy 135

meshgrid3dz 136

meshgrid4d 136

meshgridx 134

meshgridy 135

message 288

min 168

mod 189

modulus 189

monitor 70

mouse mode 33

move 116, 229

moving windows 39

mu0 138

multiplication 150

multiply 169

mv 116

natural 165

negative 150

newmode 112

newproject 112

newwizard 289

newwizardpage 289

normal 190

not 152, 154, 155

num2str 175

object tree 37

Optimization 101

or 154

orbit 259

order 54

output 157

Particle Swarm Optimization 101

path 119

pause 120

permeability 138

permittivity 138

permute 170

phase 165

pi 138

pinch 167

plot 198

plotxy 199

polar 200

polar2 200

polarimage 201

polyand 186

polyarea 183

polydiff 186

polygrow 185

polyintersect 184

polyor 186

polyxor 187

power 151

priorities 54

product 168

PSO 101

pwd 115

quit 116

rand 190

randmatrix 133

random 190

randreset 191

readdata 122

real 164

redo 260

redraw 256

Index 299


redrawmode 257

redrawoff 257

redrawon 257

replace 177

replacestring 178

reshape 170

rm 114

rotations 60

round 189

run 118

runanalysis 270

runjobs 266

running a simulation 80

runparallel 265

runsetup 235

runsweep 267

runwizard 291

save 113, 121, 122

savedata 121

savedcard 122

screen 157

script 118

scripting editor prompt command line 38

seed 191

select 227

selectall 226, 227

selectfigure 204

selectpartial 228

set 231

seteigensolver 255

setglobalmonitor 232

setglobalsource 233

setmaterial 277

setnamed 232

setplot 204

setsourcesignal 252

setview 258

shiftselect 228

shiftselectpartial 229

sign 189

simulation 35

simulation region 65

sin 162

sine 162

single quote 156

size 59, 166

solar 191

speed of light 138

spline 172

sqrt 166

square root 166

str2num 176

string to number 176

strings 155, 156

structure 58

structures group 58

substring 176

subtraction 150

sum 167

switchtolayout 208

system 116

tan 162

tangent 162

time 116

time stamp 116

timestamp 116

toolbar 30

transparency 60

transpose 175

undo 260

unselectall 227

unwrap 165

updatemodes 253

updatesourcemode 251

variables with spaces 133

view 34

view ports perspective 36

visualize 203

Reference Guide300


which 119

wizarddata 290

wizardgetdata 291

wizardoption 292

wizardwidget 289

workspace 136

write 123

z-transform 183

DEVICE Reference Guide

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