Competing superfluid and density-wave ground-states of fermionic mixtures with mass imbalance in optical lattices

Tung-Lam Dao; Antoine Georges; Massimo Capone

doi:10.1103/physrevb.76.104517

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arXiv · 0704.2660

Competing superfluid and density-wave ground-states of fermionic mixtures with mass imbalance in optical lattices

Tung-Lam Dao·Antoine Georges·Massimo Capone

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Abstract

We study the effect of mass imbalance on the phase diagram of a two-component fermionic mixture with attractive interactions in optical lattices. Using static and dynamical mean-field theories, we show that the pure superfluid phase is stable for all couplings when the mass imbalance is smaller than a limiting value. For larger imbalance, phase separation between a superfluid and a charge-density wave takes place when the coupling exceeds a critical strength. The harmonic trap induces a spatial segregation of the two phases, with a rapid variation of the density at the boundary.

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Tung-Lam Dao, Antoine Georges, Massimo Capone. 2007-04-20. Competing superfluid and density-wave ground-states of fermionic mixtures with mass imbalance in optical lattices. https://doi.org/10.1103/physrevb.76.104517

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