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Beyond the Thomas-Fermi approximation for a trapped condensed Bose-Einstein gas

Alexander L. Fetter·David L. Feder
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Abstract

Corrections to the zero-temperature Thomas-Fermi description of a dilute interacting condensed Bose-Einstein gas confined in an isotropic harmonic trap arise due to the presence of a boundary layer near the condensate surface. Within the Bogoliubov approximation, the various contributions to the ground-state condensate energy all have terms of order R^{-4}ln R and R^{-4}, where R is the number-dependent dimensionless condensate radius in units of the oscillator length. The zero-order hydrodynamic density-fluctuation amplitudes are extended beyond the Thomas-Fermi radius through the boundary layer to provide a uniform description throughout all space. The first-order correction to the excitation frequencies is shown to be of order R^{-4}.

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Alexander L. Fetter, David L. Feder. 1998-07-28. Beyond the Thomas-Fermi approximation for a trapped condensed Bose-Einstein gas. https://doi.org/10.1103/physreva.58.3185

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