Quantum Computer Aided Design Simulation and

Optimization of Semiconductor Quantum Dots

Presented

by

Yashashree WaseGraduate Student in Electrical and Computer Engineering

Contact: ywase@uidaho.edu

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Outline

• Glossary of Terms

• Introduction to QCAD

• QCAD simulator code structure

• Three core physical solvers

• Application examples

• Summary

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Glossary

• Qubit: Unit of quantum information in quantum

computing. Superposition of 0s and 1s at the same time

• Quantum dots (QD): Physical(energy) confinement to get

atomic-like structure. Artificial atom. QDs are much more

flexible than atoms.

• Double quantum dots (DQD): Two lateral quantum dots

coupled in series to avoid the effect of background spins

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Quantum Computer Aided Design (QCAD)

• Challenges in modeling QDs

• QCAD simulator targets modeling multi-dimensional

quantum devices developed for qubit application.

• It is integrated open-source finite-element-based tool

• Simulate experimental QDs to provide feedback and

guidance for experiment.

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QCAD Code Structure

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Source: Gao, X. and Nielsen, E. and Muller, R. P. and Young, R. W. and Salinger, A. G. and Bishop, N. C. and Lilly, M. P. and Carroll, M. S., Quantum computer aided design simulation and optimization of semiconductor quantum dots, Journal of Applied Physics, 114, 164302 (2013)

•Easy scripting ability

•Solves set of equations

•Extended problem space

•High simulation throughput

•Parallel computing

QCAD Core

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QD Capacitance

• QCADs ability to

compute the

capacitance between

a quantum dot and a

control gate

• Constraint one

electron in a dot

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DQD Optimization

• QCADs ability to

asses and improve

upon the design of

nano-scale devices

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Summary

• QCAD software tool developed enables design comparison

and guidance for semiconductor quantum dot devices

• High throughput of simulations through scripting,

automated meshing and web portal allows fast feedback

to experimentalist

• Self-consistent quantum models in QCAD allows for

analysis of quantum effects on device behavior (cap.etc)

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Thank you!

Your questions are valuable!

11May 19, 2016