Finite temperature phase diagram of trapped Fermi gases with population imbalance

Wei Zhang; L. -M. Duan

doi:10.1103/physreva.76.042710

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arXiv · 0706.1253

Finite temperature phase diagram of trapped Fermi gases with population imbalance

Wei Zhang·L. -M. Duan

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Abstract

We consider a trapped Fermi gas with population imbalance at finite temperatures and map out the detailed phase diagram across a wide Feshbach resonance. We take the Larkin-Ovchinnikov-Fulde-Ferrel (LOFF) state into consideration and minimize the thermodynamical potential to ensure stability. Under the local density approximation, we conclude that a stable LOFF state is present only on the BCS side of the Feshbach resonance, but not on the BEC side or at unitarity. Furthermore, even on the BCS side, a LOFF state is restricted at low temperatures and in a small region of the trap, which makes a direct observation of LOFF state a challenging task.

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Wei Zhang, L. -M. Duan. 2008-05-21. Finite temperature phase diagram of trapped Fermi gases with population imbalance. https://doi.org/10.1103/physreva.76.042710

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