Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 1

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Lecture 23

Single Photon Source;

Coherent State

Read: FQ6-7

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 2

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

coherence & 1st order correlation [g(1)] Coherence:•Temporal•Spatial

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 3

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

2nd order correlation function

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 4

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

HBT with photons

(Single) photon

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 5

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Hardware requirements/complications

• (reliable) Single photon source[multiphoton emission compromises security by giving Eve

more chances to evade detection (both Eve’s detectors click knows basis wrong)]

– Attenuated single-freq laser: photon Poisson distr, subject to multi-photons

– “on-demand” single photon source [current research]

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 6

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 7

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 8

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

On-demand single-photon source“photon gun”

An example (optical trigger)

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 9

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Questions:

•Why g2(0)>0?

•Antibunching == sub-poissonian?

Solid state sources

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 10

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Wave particle duality

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 11

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

single photons->antibunching

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 12

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Quantum nature of light

• quantized energy (photon)

• Quantized EM field

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 13

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Fox FQ’Chap7

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 14

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Light as classical EM wave (oscillator)

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 15

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Classical Harmonic Oscillator

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 16

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Light as classical EM wave (oscillator)

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 17

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Phasor diagram and field quadratures (dimensionless)

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 18

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Quantum harmonic oscillator

photon

• Zero-point fluctuationvacuum field

• Shot noise• Number-phase uncertainty

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 19

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Vacuum field

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 20

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Casimir Force

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 21

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Coherent State

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 22

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

Number phase relation

Purdue University Spring 2016 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 18 (3/24/2016) Slide 23

Introduction to Quantum Photonics & Quantum Optics

PHYS522 ECE695

(“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/