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Excited states of a dilute Bose-Einstein condensate in a harmonic trap

Alexander L. Fetter·Daniel Rokhsar
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Abstract

The low-lying hydrodynamic normal modes of a dilute Bose-Einstein gas in an isotropic harmonic trap determine the corresponding Bogoliubov amplitudes. In the Thomas-Fermi limit, these modes have large low-temperature occupation numbers, and they permit an explicit construction of the dynamic structure function $S(q,ω)$. The total noncondensate number $N'(0)$ at zero temperature increases like $R^6$, where $R$ is the condensate radius measured in units of the oscillator length. The lowest dipole modes are constructed explicitly in the Bogoliubov approximation.

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Alexander L. Fetter, Daniel Rokhsar. 1997-04-28. Excited states of a dilute Bose-Einstein condensate in a harmonic trap. https://doi.org/10.1103/physreva.57.1191

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