Ultracold atoms in a square lattice with spin-orbit coupling: Charge order, superfluidity, and topological signatures

摘要

We present an $\textit{ab initio}$, numerically exact study of attractivefermions in square lattices with Rashba spin-orbit coupling. The ground stateof this system is a supersolid, with co-existing charge and superfluid order.The superfluid is composed of both singlet and triplet pairs induced byspin-orbit coupling. We perform large-scale calculations using auxiliary-fieldquantum Monte Carlo to provide the first full, quantitative description of thecharge, spin, and pairing properties of the system. In addition tocharacterizing the exotic physics, our results will serve as essentialhigh-accuracy benchmarks for the intense theoretical and especiallyexperimental efforts in ultracold atoms to realize and understand an expandingvariety of quantum Hall and topological superconductor systems.