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Understanding the superfluid phase diagram in trapped Fermi gases

Qijin Chen·C. A. Regal·M. Greiner·D. S. Jin·K. Levin
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Abstract

Trapped ultracold Fermi gases provide a system that can be tuned between the BCS and BEC regimes by means of a magnetic-field Feshbach resonance. Condensation of fermionic atom pairs in a $^{40}$K gas was demonstrated experimentally by a sweep technique that pairwise projects fermionic atoms onto molecules. In this paper we examine previous data obtained with this technique that probed the phase boundary in the temperature-magnetic field plane. Comparison of the $^{40}$K data to a theoretically computed phase diagram demonstrates good agreement between the two.

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Qijin Chen, C. A. Regal, M. Greiner, D. S. Jin, K. Levin. 2005-12-22. Understanding the superfluid phase diagram in trapped Fermi gases. https://doi.org/10.1103/physreva.73.041601

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