Physics 500 Spring 2009

University of New Mexico

Department of Physics and Astronomy

Introduction to Laser Cooling and Trapping of Atoms

General Information

Instructor: Prof. Ivan Deutsch (my research group web page)

Phys/Astro Room 24, Phone: 277-1502

Prequisites: Physics 521-522 (or equivalent)

Overview: What began as simple technique to be used for improved spectroscopy and precision measurement has blossomed into a powerful tool for fundamental studies in low temperature physics. New applications in matter wave interferometry, quantum degenerate gases, and quantum information processing are now being actively pursued. The inventions have lead to two Nobel Prizes in physics: 1997 (for atomic laser cooling) and 2001 (for Bose-Einstein condensation). This seminar is an introduction to theory and experiment in laser cooling and trapping of neutral atoms and ions. A series of lectures for ~7 weeks will be followed by student presentations on contemporary research papers. Topics to be covered include:

• Basics of atom-photon interaction.

• Doppler cooling.

• Optical molasses and magneto-optic traps.

• Subdoppler polarization and polarization gradient cooling.

• Ion traps and resolved sideband cooling.

• Optical lattices.

• BEC and Fermi degenerate gases.

• Cold collisions.

• Quantum information processing with cold atoms.

Resource Materials:

Nobel Lectures from 1997 Prize: Chu, Cohen-Tannoudj, Phillips
Metcalf Review
Adams and Riis Reviw
BEC overview from Nobel Prize 2001
1990 Les Houches Summer School Lectures, "Atomic Motion in Laser Light", C. Cohen Tannoudji
- Chapt. 1-3., Chapt. 4-6.
Review Articles on Laser Cooling and Trapping of Atoms
- "Electromagnetic trapping of cold atoms", V I Balykin, V G Minogin and V S Letokhov, Rep. Prog. Phys. 63 1429 (2000) .
- "Atom cooling, trapping, and quantum manipulation", Carl E. Wieman, David E. Pritchard, David J. Wineland, Rev. Mod. Phys., 71, (1999).
Ion Traps
- Talk by David Wineland.
- Classic articles on cooling in ion traps.

Tentative Schedule of Lectures

Lecture	Topic
1	Overview: History of laser cooling, Classical model of force on atoms - scattering force and dipole force.
2	Quantum model: Photon scattering and ac-stark shift
3	Doppler Cooling 2: Qualitative picture
4	Doppler Cooling 2: Optical molasses and the Doppler Limit.
5	Trapping 1: Magneto-optic trap, Dipole traps
6	Subdoppler cooling 1: Intro to polarization graident cooling. Master equation for low saturation.
7	Subdoppler cooling 2: Sisyphus cooling
8	Trapping 2 - Ion traps
9	Cooling trapped particles -- The Lamb-Dicke effect. Resolved sideband laser cooling.

Student Presentations

Date	Student: Topic
4/6	Brad Chase: Creating BEC Thomas Loyd: BEC on a Chip
4/13	Xuefang Zhang: BEC Mean-Field Approximation Zhang Jiang: BEC in an Optical Lattice
4/20	Ben Baragiola: Feshbach Resonances Alexandre Tacla: BEC-BCS Transition
4/27	Lee Walsh: Polar Molecules Leigh Norris: Collective Spin Control with Cold Atoms
5/4	Carlos Riofrio: Quantum Control in Ion Traps

Review Talks: Subjects

I. Laser Cooling

Polarization Gradient Cooling (theory and experiment).
Blue Molasses (high intensity Sisyphus cooling).
Sub-recoil "dark-state" cooling: Velocity-selctive coherent population trapping (VSCPT).
Ion cooling.
Cooling neutrals into the Lamb-Dicke regime.
Sideband cooling in optical lattices.

III. Trapping

Magneto Optic Traps.
Dipole Traps.
"Atom Chips".
Trapping single neutrals.

II. Atom Optics

Atom Interferometers
- Light grattings
- Mechanical Gratings
- Ramsey Inteferometer with moti
Atom mirrors and beam splitters.
Atom laser

III. Degenerate Quantum Gases

Making/observing a BEC
Making/observing a degenerate Fermi gas.
Nonlinear atom optics.
BEC in optical lattice.

IV. Ultracold Collisions

Photoassociation spectroscopy.
Ground state collisions.
Feshbach resonance.

V. Quantum Information/Control

Wave packet engineering in ion traps.
Quantum control in optical lattices.
Quantum computing with ions.
Quantum computing with neutrals.