Spin-orbit-driven transitions between Mott insulators and finite-momentum superfluids of bosons in optical lattices

摘要

Synthetic spin-orbit coupling in ultracold atomic gases can be taken to extremes rarely found in solids.We study a two-dimensional Hubbard model of bosons in an optical lattice in the presence of spin-orbit coupling strong enough to drive direct transitions from Mott insulators to superfluids. Here we find phase-modulated superfluids with finite momentum that are generated entirely by spin-orbit coupling. We investigate the rich phase patterns of the superfluids, which may be directly probed using time-of-flight imaging of the spin-dependent momentum distribution.