Phase diagram of imbalanced fermions in optical lattices

Abstract

The zero-temperature phase diagrams of imbalanced fermions in 3D optical lattices are investigated to evaluate the validity of the Fermi-Hubbard model. It is found that depending on the filling factor, s-wave scattering strength and lattice potential, the system may fall into the normal($N$) phase, magnetized superfluid(SF${}_M$) or phase separation of $N$ and BCS state. By tuning these parameters, the superfluidity could be favorable by enhanced effective couplings or suppressed by the increased band gap. The phase profiles in the presence of a harmonic trap are also investigated under LDA, which show some exotic shell structures compared to those without the optical lattice.

5 pages, 4 figures, typos and references added

References in corpus (10)

• Evidence for Superfluidity of Ultracold Fermions in an Optical Lattice
• Direct Observation of the Superfluid Phase Transition in Ultracold Fermi Gases
• Phase diagram of a two-component Fermi gas with resonant interactions
• Pairing without Superfluidity: The Ground State of an Imbalanced Fermi Mixture
• Mean field phase diagrams of imbalanced Fermi gases near a Feshbach resonance
• Finite temperature phase diagram of a polarized Fermi gas in an optical lattice
• FFLO state in 1, 2, and 3 dimensional optical lattices combined with a non-uniform background potential
• Superfluid-Insulator Transition of Strongly Interacting Fermi Gases in Optical Lattices
• Polarized superfluidity in the attractive Hubbard model with population imbalance
• Superfluid and insulating phases of fermion mixtures in optical lattices