Gapless Superfluid in $SU(2n+1)$ Fermions Systems

Betzalel Bazak; Nir Barnea

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arXiv · 1104.1495

Gapless Superfluid in $SU(2n+1)$ Fermions Systems

Betzalel Bazak·Nir Barnea

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Abstract

We investigate the generalized Hubbard model of $(2n+1)$ Fermion species interacting via a symmetric contact attraction potential. We prove that the ground state of such system is a gapless superfluid, where a full Fermi surface coexists with a superfluid. Moreover, doing so we prove the existence of a free mode in a strongly interacting system, regardless of the potential strength. This proof holds at the mean field level. A Grassmannian Gaussian integration technique is used to deal with the problem. Our predictions may be relevant to future high-spin cold atoms experiments.

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Betzalel Bazak, Nir Barnea. 2011-04-08. Gapless Superfluid in $SU(2n+1)$ Fermions Systems. https://arxiv.org/abs/1104.1495

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