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Superfluid and insulating phases of fermion mixtures in optical lattices

M. Iskin·C. A. R. Sa de Melo
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Abstract

The ground state phase diagram of fermion mixtures in optical lattices is analyzed as a function of interaction strength, fermion filling factor and tunneling parameters. In addition to standard superfluid, phase-separated or coexisting superfluid/excess-fermion phases found in homogeneous or harmonically trapped systems, fermions in optical lattices have several insulating phases, including a molecular Bose-Mott insulator (BMI), a Fermi-Pauli (band) insulator (FPI), a phase-separated BMI/FPI mixture or a Bose-Fermi checkerboard (BFC). The molecular BMI phase is the fermion mixture counterpart of the atomic BMI found in atomic Bose systems, the BFC or BMI/FPI phases exist in Bose-Fermi mixtures, and lastly the FPI phase is particular to the Fermi nature of the constituent atoms of the mixture.

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M. Iskin, C. A. R. Sa de Melo. 2007-12-10. Superfluid and insulating phases of fermion mixtures in optical lattices. https://doi.org/10.1103/physrevlett.99.080403

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