Journal Article

Interaction-induced topological transition in spin-orbit coupled ultracold bosons

Cao, Rui, Wang, Xiansi, Dai, Jiayu, Li, Yongqiang, Tan, Hui, Yuan, Jianmin, Han, Jinsen

2023

Overview

Recent experiments in ultracold atoms have reported the realization of quantum anomalous Hall phases in spin-orbit coupled systems. Motivated by such advances, we investigate spin-orbit coupled Bose-Bose mixtures in a two-dimensional square optical Raman lattice. Complete phase diagrams are obtained via a nonperturbative real-space bosonic dynamical mean-field theory. Various quantum phases are predicted, including Mott phases with z -ferromagnetic, xy -antiferromagnetic and vortex textures, and superfluid phases with the exotic spin orders, induced by the competition between the lattice hopping and spin-orbit coupling. To explain the underlying physics in the Mott regime, an effective Hamiltonian is derived based on second-order perturbation theory, where pseudospin order stems from the interplay of effective Dzyaloshinskii-Moriya superexchange and Heisenberg interactions. In the presence of the Zeeman field, the competition of strong interaction and Zeeman energy facilitates a topological phase, which is confirmed both by the nontrivial topological Bott index and spectral function with topological edge states. Our work indicates that spin-orbit coupling can induce rich non-Abelian topological physics in strongly correlated ultracold atomic systems.

• Publisher: Science China Press,Springer Nature B.V
• Subject: Antiferromagnetism / Astronomy / Bosons / Classical and Continuum Physics / Electromagnetism / Ferromagnetism / Fluids / Hamiltonian functions / Mean field theory / Observations and Techniques / Perturbation theory / Phase diagrams / Phase transitions / Phases / Physics / Physics and Astronomy / Spin-orbit interactions / Strong interactions (field theory) / Superfluidity / Topology / Ultracold atoms