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Dilute Bose-Einstein Condensate in a Trap: Characteristic Lengths and Critical Velocities

Alexander L. Fetter
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Abstract

The Bogoliubov approximation and the Gross-Pitaevskii equation characterize the effect of repulsive interactions on a dilute ideal Bose-Einstein gas in a spherical harmonic trap. For large $N$, the interactions expand the condensate relative to an ideal Bose gas; both the speed of sound and critical angular velocity $Ω_{c1}$ for creation of a quantized vortex depend crucially on the interparticle repulsion through the coherence length $ξ$.

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Alexander L. Fetter. 1997-09-18. Dilute Bose-Einstein Condensate in a Trap: Characteristic Lengths and Critical Velocities. https://arxiv.org/abs/cond-mat/9709207

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