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arXiv · 0711.0653

Destroying superfluidity by rotating a Fermi gas at unitarity

I. Bausmerth·A. Recati·S. Stringari
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Abstract

We study the effect of the rotation on a harmonically trapped Fermi gas at zero temperature under the assumption that vortices are not formed. We show that at unitarity the rotation produces a phase separation between a non rotating superfluid (S) core and a rigidly rotating normal (N) gas. The interface between the two phases is characterized by a density discontinuity $n_{\rm N}/n_{\rm S}= 0.85$, independent of the angular velocity. The depletion of the superfluid and the angular momentum of the rotating configuration are calculated as a function of the angular velocity. The conditions of stability are also discussed and the critical angular velocity for the onset of a spontaneous quadrupole deformation of the interface is evaluated.

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I. Bausmerth, A. Recati, S. Stringari. 2008-01-23. Destroying superfluidity by rotating a Fermi gas at unitarity. https://doi.org/10.1103/physrevlett.100.070401

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