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Finite temperature excitations of Bose gases in anisotropic traps

J. Reidl·A. Csordás·R. Graham·P. Szépfalusy
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Abstract

The mode frequencies of a weakly interacting Bose gas in a magnetic trap are studied as a function of the anisotropy of the trap. As in earlier works the generalized Hartree-Fock-Bogoliubov equations within the Popov approximation (HFB-Popov) are used for our calculations. The new feature of our work is the combined use of a mode expansion in a finite basis and a semiclassical approximation of the highly excited states. The results are applied to check the accuracy of the recently suggested equivalent zero-temperature condensate (EZC) approximation which involves a much simpler model.

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J. Reidl, A. Csordás, R. Graham, P. Szépfalusy. 1998-11-02. Finite temperature excitations of Bose gases in anisotropic traps. https://doi.org/10.1103/physreva.59.3816

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