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arXiv · 1307.2655

Collective excitations of an imbalanced fermion gas in a 1D optical lattice

R. Mendoza·Mauricio Fortes·M. A. Solís
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Abstract

The collective excitations that minimize the Helmholtz free energy of a population-imbalanced mixture of a $^{6}$Li gas loaded in a quasi one-dimensional optical lattice are obtained. These excitations reveal a rotonic branch after solving the Bethe-Salpeter equation under a generalized random phase approximation based on a single-band Hubbard Hamiltonian. The phase diagram describing stability regions of Fulde-Farrell-Larkin-Ovchinnikov and Sarma phases is also analyzed.

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R. Mendoza, Mauricio Fortes, M. A. Solís. 2013-07-10. Collective excitations of an imbalanced fermion gas in a 1D optical lattice. https://doi.org/10.1007/s10909-013-0926-2

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