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Comment on "Superfluid stability in the BEC-BCS crossover"

Daniel E. Sheehy·Leo Radzihovsky
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Abstract

We point out an error in recent work by Pao, Wu, and Yip [Phys. Rev.B {\bf 73}, 132506 (2006)], that stems from their use of a necessary but not sufficient condition [positive compressibility (magnetic susceptibility) and superfluid stiffness] for the stability of the ground state of a polarized Fermi gas. As a result, for a range of detunings their proposed ground-state solution is a local maximum rather than a minimum of the ground state energy, which thereby invalidates their proposed phase diagram for resonantly interacting fermions under an imposed population difference.

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Daniel E. Sheehy, Leo Radzihovsky. 2007-05-28. Comment on "Superfluid stability in the BEC-BCS crossover". https://doi.org/10.1103/physrevb.75.136501

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