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arXiv · cond-mat/0506437

Superfluid stability in BEC-BCS crossover

C. -H. Pao·Shin-Tza Wu·S. -K. Yip
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Abstract

We consider a dilute atomic gas of two species of fermions with unequal concentrations under a Feshbach resonance. We find that the system can have distinct properties due to the unbound fermions. The uniform state is stable only when either (a) beyond a critical coupling strength, where it is a gapless superfluid, or (b) when the coupling strength is sufficiently weak, where it is a normal Fermi gas mixture. Phase transition(s) must therefore occur when the resonance is crossed.

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C. -H. Pao, Shin-Tza Wu, S. -K. Yip. 2005-06-17. Superfluid stability in BEC-BCS crossover. https://doi.org/10.1103/physrevb.73.132506

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