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arXiv · 0906.1937

Polarized Fermi gases in asymmetric optical lattices

Xiaoling Cui·Yupeng Wang
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Abstract

The zero-temperature phase diagrams of imbalanced two-species Fermi gases are investigated in asymmetric optical lattices with arbitrary potential depths, based on the exact spectrum instead of the Fermi-Hubbard model. We study the effect of lattice potentials and atomic densities to the fully paired Bardeen-Cooper-Schrieffer (BCS) state and particularly the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state. It is found that the increasing lattice potential favors BCS at low densities because of the enhanced effective coupling; whereas FFLO is favored at intermediate densities when the system undergoes a dimensional crossover. Finally using local density approximation we study the evolution of phase profile in the presence of external harmonic traps by merely tuning the lattice potentials.

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Xiaoling Cui, Yupeng Wang. 2010-02-23. Polarized Fermi gases in asymmetric optical lattices. https://doi.org/10.1103/physreva.81.023618

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