Quantum Anomalous Hall Effect with Cold Atoms Trapped in a Square Lattice

TL;DR

This paper proposes an experimental setup using cold atoms in a square lattice to realize and detect the quantum anomalous Hall effect, including methods for observing topological phase transitions via light Bragg scattering.

Contribution

It introduces a feasible scheme to realize and detect the quantum anomalous Hall effect in cold atom systems with a novel optical lattice and gauge potential.

Findings

Quantized anomalous Hall conductivity calculated via Chern number

Detection of topological phase transition through light Bragg scattering

Feasibility demonstrated for experimental realization

Abstract

We propose an experimental scheme to realize and detect the quantum anomalous Hall effect in an anisotropic square optical lattice which can be generated from available experimental set-ups of double-well lattices with minor modifications. A periodic gauge potential induced by atom-light interaction is introduced to give a Peierls phase for the nearest-neighbor site hopping. The quantized anomalous Hall conductivity is investigated by calculating the Chern number as well as the chiral gapless edge states of our system. Furthermore, we show in detail the feasability for its experimental detection through light Bragg scattering of the edge and bulk states with which one can determine the topological phase transition from usual insulating phase to quantum anomalous Hall phase.