## Characterizing the coherence of Bose-Einstein condensates and atom lasers

Optics Express, Vol. 1, Issue 10, pp. 284-292 (1997)

http://dx.doi.org/10.1364/OE.1.000284

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### Abstract

For a dilute, interacting Bose gas of magnetically-trapped atoms at temperatures
below the critical temperature *T*_{0} for Bose-Einstein
condensation, we determine the second-order coherence function
*g*^{(2)}(**r**_{1},
**r**_{2}) within the framework of a finite-temperature
quantum field theory. We show that, because of the different spatial
distributions of condensate and thermal atoms in the trap,
*g*^{(2)}(**r**_{1},
**r**_{2}) does not depend on |**r**_{1} -
**r**_{2}| alone. This means that the experimental
determinations of *g*^{(2)} reported to date give only
its spatial average. Such an average may underestimate the degree of coherence
attainable in an atom laser by judicious engineering of the output coupler.

© Optical Society of America

**OCIS Codes**

(020.7010) Atomic and molecular physics : Laser trapping

(030.1640) Coherence and statistical optics : Coherence

(140.3320) Lasers and laser optics : Laser cooling

**ToC Category:**

Focus Issue: Fluctuations and oscillations of Bose-Einstein

**History**

Original Manuscript: September 10, 1997

Published: November 10, 1997

**Citation**

Robert Dodd, Charles Clark, Mark Edwards, and Keith Burnett, "Characterizing the coherence of Bose-Einstein
condensates and atom lasers," Opt. Express **1**, 284-292 (1997)

http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-1-10-284

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