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Deformed Fermi surfaces in ultracold Fermi gases

Armen Sedrakian·Jordi Mur-Petit·Artur Polls·Herbert Müther
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Abstract

The superfluid transition in an ultracold two-component atomic Fermi gas is analyzed in the case where the two components have different densities. We describe a superfluid state which spontaneously breaks the rotational-symmetry by deforming the Fermi surfaces of both species into ellipsoidal form. At relatively large hyperfine-spin asymmetries, this deformation is shown to help the appearance of pairing, which in the rotationally-symmetric (BCS) case would be forbidden by Pauli blocking. The prospects for experimental detection of such a deformed Fermi surface phase are discussed.

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Armen Sedrakian, Jordi Mur-Petit, Artur Polls, Herbert Müther. 2006-04-24. Deformed Fermi surfaces in ultracold Fermi gases. https://arxiv.org/abs/cond-mat/0404577

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