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arXiv · 0706.3819

Condensate Fraction of a Two-Dimensional Attractive Fermi Gas

Luca Salasnich
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Abstract

We investigate the Bose-Einstein condensation of fermionic pairs in a two-dimensional uniform two-component Fermi superfluid obtaining an explicit formula for the condensate density as a function of the chemical potential and the energy gap. By using the mean-field extended BCS theory, we analyze, as a function of the bound-state energy, the off-diagonal long-range order in the crossover from the Bardeen-Cooper-Schrieffer (BCS) state of weakly-bound Cooper pairs to the Bose-Einstein Condensate (BEC) of strongly-bound molecular dimers.

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Luca Salasnich. 2007-06-26. Condensate Fraction of a Two-Dimensional Attractive Fermi Gas. https://doi.org/10.1103/physreva.76.015601

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