arXiv:cond-mat/0610437 · Physical Review Letters

Attractive Fermi Gases with Unequal Spin Populations in Highly Elongated Traps

Giuliano Orso

Published Feb 14, 2007• 262 citations

Abstract

We investigate two-component attractive Fermi gases with imbalanced spin populations in trapped one-dimensional configurations. The ground state properties are determined with the local density approximation, starting from the exact Bethe-ansatz equations for the homogeneous case. We predict that the atoms are distributed according to a two-shell structure: a partially polarized phase in the center of the trap and either a fully paired or a fully polarized phase in the wings. The partially polarized core is expected to be a superfluid of the Fulde-Ferrell-Larkin-Ovchinnikov type. The size of the cloud as well as the critical spin polarization needed to suppress the fully paired shell are calculated as a function of the coupling strength.

DOI: 10.1103/physrevlett.98.070402

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