From the Cooper problem to canted supersolids in Bose-Fermi mixtures.

Competing supersolids of Bose-Bose mixtures in a triangular lattice

Exotic paired states with anisotropic spin-dependent Fermi surfaces.

We propose a model for realizing exotic paired states in cold Fermi gases by using a spin-dependent optical lattice to engineer mismatched Fermi surfaces for each hyperfine species. The BCS phase diagram shows a stable paired superfluid state with coexisting pockets of momentum space with gapless unpaired carriers, similar to the Sarma state in polarized mixtures, but in our case the system is ...

آرام کردن مایع فرمی: جدال با علامتهای فرمیونی غیر مستقیم

 The fermion sign problem is studied in the path integral formalism. The standard picture of Fermi liquids is first critically analyzed, pointing out some of its rather peculiar properties. The insightful work of Ceperley in constructing fermionic path integrals in terms of constrained world-lines is then reviewed. In this representation, the minus signs associated with Fermi-Dirac statistics a...

Density waves and supersolidity in rapidly rotating atomic Fermi gases.

We study theoretically the low-temperature phases of a two-component atomic Fermi gas with attractive s-wave interactions under conditions of rapid rotation. We find that, in the extreme quantum limit, when all particles occupy the lowest Landau level, the normal state is unstable to the formation of charge density wave (CDW) order. At lower rotation rates, when many Landau levels are occupied,...

Exotic paired phases in ladders with spin-dependent hopping

Fermions in two-dimensions (2D) when subject to anisotropic spin-dependent hopping can potentially give rise to unusual paired states in unpolarized mixtures that can behave as non-Fermi liquids. One possibility is a fully paired state with a gap for fermion excitations in which the Cooper pairs remain uncondensed. Such a “Cooper-pair Bose-metal” phase would be expected to have a singular Bose-...