Quasiparticle Berry curvature and Chern numbers in spin-orbit coupled bosonic Mott insulators

TL;DR

This paper investigates the topological properties of bosonic Mott insulators with spin-orbit coupling, revealing that interactions can generate nontrivial Berry curvature and Chern numbers, which can be experimentally measured in cold-atom systems.

Contribution

It provides a theoretical framework linking quasiparticle Berry curvature and Chern numbers to many-body interactions in spin-orbit coupled bosonic Mott insulators, supported by strong-coupling perturbation calculations.

Findings

Berry curvature and Chern numbers can be generated purely by interactions.

Quasiparticle dispersions and spectral weights are computed for experimental relevance.

Theoretical predictions are accessible via cold-atom experimental measurements.

Abstract

We study the ground-state topology and quasiparticle properties in bosonic Mott insulators with two- dimensional spin-orbit couplings in cold atomic optical lattices. We show that the many-body Chern and spin-Chern number can be expressed as an integral of the quasihole Berry curvatures over the Brillouin zone. Using a strong-coupling perturbation theory, for an experimentally feasible spin-orbit coupling, we compute the Berry curvature and the spin Chern number and find that these quantities can be generated purely by interactions. We also compute the quasiparticle dispersions, spectral weights, and the quasimomentum space distribution of particle and spin density, which can be accessed in cold-atom experiments and used to deduce the Berry curvature and Chern numbers.