We point out an error in recent work by Pao, Wu, and Yip [Phys. Rev. B 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. © 2007 The American Physical Society.
Publication Source (Journal or Book title)
Physical Review B - Condensed Matter and Materials Physics
Sheehy, D., & Radzihovsky, L. (2007). Comment on "superfluid stability in the BEC-BCS crossover". Physical Review B - Condensed Matter and Materials Physics, 75 (13) https://doi.org/10.1103/PhysRevB.75.136501