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Collective excitations of Bose-Einstein condensed gases at finite temperatures

R. J. Dodd·M. Edwards·C. W. Clark·K. Burnett
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Abstract

We have applied the Popov version of the Hartree-Fock-Bogoliubov (HFB) approximation to calculate the finite-temperature excitation spectrum of a Bose-Einstein condensate (BEC) of $^{87}$Rb atoms. For lower values of the temperature, we find excellent agreement with recently-published experimental data for the JILA TOP trap. In contrast to recent comparison of the results of HFB--Popov theory with experimental condensate fractions and specific heats, there is disagreement of the theoretical and recent experimental results near the BEC phase transition temperature.

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R. J. Dodd, M. Edwards, C. W. Clark, K. Burnett. 1997-08-19. Collective excitations of Bose-Einstein condensed gases at finite temperatures. https://doi.org/10.1103/physreva.57.r32

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