Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 1

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

Lecture 18Photon Entanglement and Teleportation

Reminder: •Lecture notes taker: Zhou Fang•HWK4 due date extended to 4/14 Monday•Condensed Matter Seminar Friday 3:30pm on QD-Si energy transfer (excitonic)

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 2

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

Lectures Topics Lecture 1 (1/13) Overview (FQ1+) Lecture 2 (1/15) Review Classical Optics (FQ2; FS1-2) No Class on 1/20 Monday (MLK day) Lecture 3 (1/22) Review Quantum Mechanics, birth of photons (FQ3+) Lecture 4 (1/27) Quantum Information, cryptography & communication (FQ12) Lecture 5 (1/29) Radiative Transitions in Atoms & Molecules (FQ4; FS8.2) Lecture 6 (2/03) Radiative/Inter-band transition in solids (FS3, FS7.3.2) Lecture 7 (2/05) Masers & Lasers: CW, pulsed, frequency comb, Xasers Lecture 8 (2/10) Photon Statistics (FQ5) Lecture 9 (2/12) Photon Correlation (FQ6), extension to other (quasi)particles Lecture 10 (2/17) Coherent, Squeezed & Number states (FQ7,8) Lecture 11 (2/19) Resonant Light-atom interaction, density matrices, Rabi oscillation (FQ9) Lecture 12 (2/24) Solid state quantum structures: wells, wires and dots (FS6) Lecture 13 (2/26) Laser cooling of atoms & solids (FQ11+) Lecture 14 (3/03) Cold atoms & atom optics, atom lasers (given by TA R. Niffenegger) Lecture 15 (3/05) TBD (Special topics/APS/coherent control) Lecture 16 (3/10) Excitons and Polaritons (FS4+) Lecture 17 (3/12) Luminescence, Luminescence/NV centers & quantum emitters (FS5,9+) No classes on 3/17 & 3/19 (Spring Break) Lecture 18 (3/24) EIT, slow light (Agarwal) & coherent control Lecture 19 (3/26) Quantum entanglement, memory & teleportation (FQ14) Lecture 20 (3/31) Atoms in cavities, Jaynes-Cummings model (FQ10) Lecture 21 (4/02) Cavity QED/circuit QED, optomechanics Lecture 22 (4/07) Quantum Computing, photon based QC (FQ13+) Lecture 23 (4/09) Quantum Computing systems: ions, Rydberg atoms, molecules Lecture 24 (4/14) Quantum Computing systems: superconductor/cQED, quantum dots, NMR Lecture 25 (4/16) Photonics with nanomaterials: CNT, graphene & 2D materials (FS8+) Lecture 26 (4/21) Phonons/Vibrons and Raman spectroscopy, CARS (FS10) Lecture 27 (4/23) Special topics: Quantum Sensing & Photodetectors, applications Lecture 28 (4/28) Special topics: Optically synthetic gauge fields/topological/quantum

matter, quantum emulation, student presentations Lecture 29 (4/30) Special topics: Casimir, (quantum) plasmonics etc. student presentations Final Exam on (TBD)

Course OutlinePart 1: basic review:Optics+Quantum;

Part 2: Basic Light-matter interaction; laser;

Part 3: Quantum Optics of photons

Part 4: More advanced light-matter interaction

Part 5: Quantum information/photonics/applications

Subject to change;Check updates on course web/wiki

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 3

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

Today’s Plan

• Quantum Entanglement and Teleportation (photons)

[FQ Chap 14]

• Student Presentation of Special Topic: Boson Sampling (photons)

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 4

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

Quantum Entanglement & Teleportation (of Photons)

Beam Me Up Scotty? A Q&A about Quantum Teleportation with H. Jeff Kimble ---- Scientific American 2008

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 5

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

Entangled States (“Bell States”)A “many-body” (at least 2 particles) state:Cannot be factored into “product” states (|particle1>|particle2> etc.)

Example:

(perfect positive correlation) (perfect negative correlation)

• Can be generated from product state by CNOT gate

Entanglement also important for many-body correlated quantum states, “topological order”, eg. in FQHE (cf. Haldane, Bernevig, …)

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 6

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

Generate Entangled States (correlated photon pairs)

Einstein-Podolsky-Rosen (EPR)-Bohm

Individual measurement results: random yet correlated b/t two detectors

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 7

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

Schrodinger Cat?

But:Decoherence in macro object(environment)

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 8

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

Generation of entangled photon pairs• Cascade in atomic transitions (eg. Ca)

• Down-conversion in nonlinear crystal

(“type-II”)

Phase matching

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 9

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

Single Photon Interferometer

Hong-Ou-Mandelinterferometer

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 10

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

Quantum Theory of HBT Experiment

(normal ordering)

(vac)

classical quantum

input

for |1>=|n>(number state)

for |1>=|>(coherent state)=1

(=0 “anti-bunching” for single photon)

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 11

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

“Which path” interferometer• Possibility to know destroys

interference

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 12

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

“Bell’s theorem/inequality” (for local hidden variables) ---- violation proves no LHVs

QMLHV

“in-flight” changeno >c info

Aspect’82

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 13

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

Teleportation

Quantum state (info), not the physical qubit/entity (eg. photon)

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 14

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

EPR/Bell-assisted teleportation

Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 16 (3/31/2014) Slide 15

Introduction to Quantum Optics & Quantum Photonics

PHYS522 ECE695

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

Nature 390, 575-579 (11 December 1997) | doi:10.1038/37539; Received 16 October 1997; Accepted 18 November 1997

Experimental quantum teleportationDik Bouwmeester1, Jian-Wei Pan1, Klaus Mattle1, Manfred Eibl1, Harald Weinfurter1 & Anton Zeilinger1