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arXiv · 1103.1064

Condensate formation with three-component ultracold fermions

Abstract

We investigate the formation of Bose-Einstein condensation and population imbalance in a three-component Fermi superfluid by increasing the U(3) invariant attractive interaction. We consider the system at zero temperature in three dimensions and also in two dimensions. Within the mean-field theory, we derive explicit formulas for number densities, gap order parameter, condensate density and condensate fraction of the uniform system, and analyze them in the crossover from the Bardeen-Cooper-Schrieffer (BCS) state of Cooper pairs to the Bose-Einstein Condensate (BEC) of strongly-bound molecular dimers. In addition, we study this Fermi mixture trapped by a harmonic potential: we calculate the density profiles of the three components and the condensate density profile of Cooper pairs in the BCS-BEC crossover.

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Luca Salasnich. 2011-03-05. Condensate formation with three-component ultracold fermions. https://doi.org/10.1103/physreva.83.033630

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