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Intermediate temperature superfluidity in an atomic Fermi gas with population imbalance

Chih-Chun Chien·Qijin Chen·Yan He·K. Levin
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Abstract

We derive the underlying finite temperature theory which describes Fermi gas superfluidity with population imbalance in a homogeneous system. We compute the pair formation temperature and superfluid transition temperature $T_c$ and superfluid density in a manner consistent with the standard ground state equations, and thereby present a complete phase diagram. Finite temperature stabilizes superfluidity, as manifested by two solutions for $T_c$, or by low $T$ instabilities. At unitarity the polarized state is an ``intermediate temperature superfluid".

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Chih-Chun Chien, Qijin Chen, Yan He, K. Levin. 2006-09-05. Intermediate temperature superfluidity in an atomic Fermi gas with population imbalance. https://doi.org/10.1103/physrevlett.97.090402

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