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Trapped Bose-Einstein condensates at finite temperature: a two-gas model

R. J. Dodd·K. Burnett·Mark Edwards·Charles W. Clark
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Abstract

A simple picture describes the results of recent treatments of partially-condensed, dilute, trapped Bose gases at temperature T > 0. The condensate wavefunction is nearly identical to that of a T=0 condensate with the same number of condensate atoms, N_0. The cloud of non-condensed atoms is described by the statistical mechanics of an ideal Bose gas in the combined potentials of the magnetic trap and the cloud-condensate interaction. We provide a physical motivation for this result, show how it emerges in the Hartree-Fock-Bogoliubov-Popov approximation, and explore some of its implications for future experiments.

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R. J. Dodd, K. Burnett, Mark Edwards, Charles W. Clark. 1997-12-24. Trapped Bose-Einstein condensates at finite temperature: a two-gas model. https://arxiv.org/abs/cond-mat/9712286

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