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Gapless finite-$T$ theory of collective modes of a trapped gas

D. A. W. Hutchinson·R. J. Dodd·K. Burnett
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Abstract

We present predictions for the frequencies of collective modes of trapped Bose-condensed $^{87}$Rb atoms at finite temperature. Our treatment includes a self-consistent treatment of the mean-field from finite-$T$ excitations and the anomolous average. This is the first gapless calculation of this type for a trapped Bose-Einstein condensed gas. The corrections quantitatively account for the downward shift in the $m=2$ excitation frequencies observed in recent experiments as the critical temperature is approached.

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D. A. W. Hutchinson, R. J. Dodd, K. Burnett. 1998-05-05. Gapless finite-$T$ theory of collective modes of a trapped gas. https://doi.org/10.1103/physrevlett.81.2198

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