Physics 8.422 Spring 2017


                             Atomic and optical Physics







Prof. Wolfgang Ketterle



Prof. Isaac Chuang




Sergio Cantu



Woo Chang Chung



Junru Li



Jules Stuart



Zackary Vandeiro



Joanna Keseberg





Lectures:     Mondays, Wednesdays (and some Fridays)

                        See calendar for schedule:  Course info and calendar

1:00-2:30, Room 26-142

                        First day of classes: Wed, 2/8

Office hours:         Wolfgang Ketterle:  Wed 2:30-3:30 or by appointment (just send an e-mail ….)

                                    TAs:  announced on problem sets, and by appointment



Homework drop off:  In class, or in 26-237

Paper HW #1   due March 13   Solutions

Paper HW #2   due May 5   Solutions


TA lecture on Friday, 5/12, 1-2:30 in 26-214 (different classroom)


Due dates:

Module 4: May 1 HW #1, #2,      May 5 Paper HW,       May 8  HW #3, #4


Term papers due:  5/18


Main topics:

·  Quantum states and dynamics of photons

·  Photon-Atom interactions: basics and semiclassical approximations

·  Photon-Atom interactions: open system dynamics, optical Bloch equations

·  Applications and limits of the optical Bloch equations: dressed atoms, light force, decoherence

·  Cold atoms, quantum states, and quantum dynamics: quantum algorithms and protocols, ion traps,
    magnetic traps, evaporative cooling, Bose-Einstein condensation


Web Site for 2013       2015 (Martin Zwierlein)          Web Site for 8.421


Atomic Physics Wiki with Typed Lecture Notes



MITx site for 8.421 with lecture videos and online problems

Module 1:

Module 2:

Module 3:

Module 4:

Module 5:


For gain  access to the MITx course site, please enter your edx user ID here:



MIT Stellar grade management                            Course requirements

Course info and calendar                            Recommended books




Module 1:  Quantum States and Dynamics of Photons


Topic 1: Photons and Statistics

Class notes 2013:  Quantum states of light

clicker questions 2/15/2017


Book chapters:

Loudon, chapter 3; Weissbluth, 4.4-4.8

Further reading:

·         Yamamoto and Rempe group papers (example of single photon g(2)(tau) measurement)

·         Yamamoto paper on Generation of number states (see the nice quasi probability plots)

·         Kimble/Mandel 1977 paper: first antibunching of photons

·         Scully paper:  what is a photon, and why the photoelectric effect can be understood semi-classically

·         The Dual Nature of Light as Reflected in the Nobel Archives link



Topic 2: Non-classical light and squeezed states (2/21)

Class notes 2013:  Non-classical light


Book chapters:

Weissbluth, 4.9 .  Section on squeezed states

Further reading:

·         H.J. Kimble, Quantum fluctuations in quantum optics, in Les Houches 1990.  Extensive and advanced treatment of squeezed light.

·         R.W. Henry and S. C. Glotzer, A squeezed-state primer, Am. J. Phys. 56, 318 (1988).  Basic discussion using only elementary quantum mechanics.

·         M.C. Teich and B. E. A. Saleh Squeezed and AntiBunched Light, Physics Today, June 1990.   Popular article on non-classical light.

·         Generation of squeezed states, classical squeezing: F. DiFilippo et al, Classical Amplitude Squeezing for Precision Measurements. PRL, 68, 2859 (1992).

·         Teleportation:  Furusawa et al, Unconditional Quantum Teleportation. Science, 282, 706 (1998) .

·         Beam splitter and homodyne detection:  B.L. Schumaker, “Noise in homodyne detection”, Optics Letters 9, 189 (1984)

·         Experiments with squeezed light

o   Ling-An Wu, H.J. Kimble, J.L. Hall, H. Wu, “Generation of Squeezed States by Parametric Down Conversion”, PRL 57, 2520 (1986)

o   Min Xiao, Ling-An Wu, H.J. Kimble, “Precision Measurement beyond the Shot-Noise Limit”, PRL 59, 279 (1987)

o   E.S. Polzik, J. Carri, H.J. Kimble, “Spectroscopy with Squeezed Light”, PRL 68, 3020 (1992)


Topic 3: Single photons (2/22)

Class notes 2013:  Single photons

·         Phase gates with single photons:  Physics Viewpoint   Rempe group 1    Rempe group 2    Vuletic group

·         Quantum logic with photons:  Review paper

·         Quantum amplifier      Caves    Stenholm     Wiseman


Topic 4: Entangled photons (3/1)

Class notes 2013


C. A. Sackett, D. Kielpinski, B. E. King, C. Langer, V. Meyer, C. J. Myatt, M. Rowe, Q. A. Turchette, W. M. Itano, D. J. Wineland, C. Monroe, “Experimental entanglement of four particles”, Nature 404, 256 (2000)


Excerpts from Nielsen and Chuang Quantum Computation and Quantum Information on Schmidt Decomposition


Topic 5: Interferometry and metrology (3/1)

Class notes 2013


·         Gravitational wave detection:

C.M. Caves, “Quantum-mechanical noise in an interferometer”, Phys. Rev. D 23, 1693-1708 (1981)

·         Heisenberg limited interferometry

Vittorio Giovannetti, Seth Lloyd, Lorenzo Maccone, “Quantum-Enhanced Measurements: Beating the Standard Quantum Limit”, preprint quant-ph/0412078

Proposal for atom interferometry:

P. Bouyer, M. A. Kasevich, “Heisenberg-limited spectroscopy with degenerate Bose-Einstein gases”, PRA 56, R1083 (1997)

Creation of correlated states with Bose-Einstein condensates:

J.M. Vogels, J. K. Chin, and W. Ketterle, “Coherent Collisions between Bose-Einstein Condensates”, PRL 90, 030403 (2003).


Topic 6: g(2) for light and atoms (3/1)

Class notes 2013

Highly recommended:  Paper on photon-reduced thermal light Optics Letters 2013


Reading: some pages from Gordon Baym, Lectures on Quantum Mechanics

PRL on HBT experiment with cold atoms  1996 paper , first such experiment
2007 Nature paper
on HBT with helium atoms


Hong-0u-Mandel effect

With light:  Two ion interference Monroe 2007

With electrons:  Perspective    Paper

With atoms:  2014 Science paper on Hong-Ou-Mandel effect with two atoms in a double-well

With many atoms:  Greiner entanglement 2015


Class notes (3/6/2017) on photon measurement and how a fictitious measurement leads to a master equation for the light



Module 2: Atom-photon interactions


Background: The QED Hamiltonian

Viewgraphs used in the class video:  Download


The discussion follows the appendix in Atom –Photon Interactions.

Please read pp. 621 – 643   Download

Further reading:

A 500-page derivation and discussion of the basic equations of QED can be found in

·        Cohen-Tannoudji, Claude, Dupont-Roc, Jaques, and Grynberg, Gilbert, Photons & Atoms, Wiley-Interscience, 1997.

I would recommend consulting this book whenever you want to know more about the “exact” formulation of the theory.  I am always amazed how easily you can open this book in the middle and still understand the explanations.


Topic 1: Interactions between light and atoms using Feynman diagrams

Class notes 2013

API see pp. 15-21 and Complement A_I


First example of “engineering the vacuum”:

Daniel Kleppner, Inhibited Spontaneous Emission, PRL 47, 233 (1981)


What is a virtual photon?  Web site


Topic 2: van der Waals and Casimir interactions

Class notes 2013        Class notes 2013 on Casimir force between two plates

see API, pp. 118-126

Reading:    four pages course notes from Dan Kleppner (on Casimir force between capacitors)

Physics Today paper by L. Spruch (Nov. 1986, p. 37)

Casmir force between two metal plates:

Copies from Serge Haroche’s summer school notes

Jaffe paper on Casimir force and zero-point energy


Concept questions module 2 (class notes 3/23/2017)


Topic 3: Resonant scattering

Class notes 2013

Reading:  API, Chapter III

Further reading:  J. Dalibard, J. Dupont-Roc and C. Cohen-Tannoudji, Vacuum fluctuations and radiation reaction: identification of their respective contributions, J. Physique 43, 1617-1638 (1982).

Experimental observation of non-exponential decay Raizen paper  Two theoretical papers  Paper 1    Paper 2



Module 3:  Optical Bloch equations and open system dynamics


Topic 1: Derivation of optical Bloch equations

Class notes 2013


Topic 2: Solutions of the optical Bloch equations - emission spectrum


Topic 3: Solutions of the optical Bloch equations - steady state and cavity QED

Class notes 2013

Reading:  API 257 – 333

NEW:  Quantum Zeno effect – slow down of dynamics by decoherence:  experimental and theoretical paper


Topic 4: Unraveling quantum open system dynamics

Class notes 2013

Original 1992 paper on QMC wave function method Link



Module 4:  Laser cooling


Topic 1: Light forces

Topic 2: Applications of the spontaneous light force

Class notes 2013  part 1  part 2

Reading: API 370 – 379
First realization of molasses Link

Spontaneous light force traps

Magneto-optical trap, Optical Earnshaw theorem

W.D. Phillips, Laser cooling and trapping of neutral atoms, in Laser Manipulation of Atoms and Ions, edited by E. Arimondo, W.D. Phillips, and F. Strumia, Proceedings of the International School of Physics “Enrico Fermi”, Course CXVIII (North-Holland, Amsterdam, 1992) Download

pp. 316 – 355 has a nice summary on dipole traps and raditation pressure traps

Original papers:

            Optical Earnshaw theorem (OET):  Ashkin and Gordon

            How to circumvent the OET:  Pritchard et al.

            Realization of the MOT:  Raab et al.


Topic 3: Dressed atoms

Topic 4: Dipole forces within the dressed atom picture

Class notes 2013  part 1  part 2

Advanced reading on friction force in a standing wave

pp. 34-35 in :
C. Cohen-Tannoudji, “Atomic Motion in Laser Light”, in “Fundamental Systems in Quantum Optics”, Les Houches, Session LIII, 1990, ed. by J. Dalibard, J.M. Raimond and J. Zinn Justin, pp. 1-164 (Elsevier Science Publisher B.V., 1992, Link

J.P. Gordon and A. Ashkin, PRA 21, 1606 (1980) Link

            Dressed atom and dipole forces

            Reading:  API Chapter VI – worth reading!

Important paper:

J. Dalibard and C. Cohen-Tannoudji, JOSA B 1985  Link


Topic 5: Techniques for cooling to ultralow temperatures

Class notes 2013

Magnetic trapping

Further reading: W. K., D.S. Durfee, D.M. Stamper-Kurn, Varenna Lecture Notes 1999, pp. 80-89

Evaporative cooling

Further reading:: W. Ketterle and N.J. van Druten, Adv. At. Mol. Opt. Phys. 37, 181-236 (1986).  Relevant pages:  pp. 181-193