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Finite temperature effects in trapped Fermi gases with population imbalance

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

We study the finite temperature $T$ behavior of trapped Fermi gases as they undergo BCS-Bose Einstein condensation (BEC) crossover, in the presence of a population imbalance. Our results, in qualitative agreement with recent experiments, show how the superfluid phase transition is directly reflected in the particle density profiles. We demonstrate that at $ T \neq 0$ and in the near-BEC and unitary regimes, the polarization is excluded from the superfluid core. Nevertheless a substantial polarization fraction is carried by a normal region of the trap having strong pair correlations, which we associate with noncondensed pairs or the ``pseudogap phase''.

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Chih-Chun Chien, Qijin Chen, Yan He, K. Levin. 2006-05-28. Finite temperature effects in trapped Fermi gases with population imbalance. https://doi.org/10.1103/physreva.74.021602

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