Dissipative preparation of Chern insulators

TL;DR

This paper introduces a method to dissipatively prepare a topological Chern insulator state in a non-equilibrium quantum system using short-range interactions, with potential experimental realization in cold atom setups.

Contribution

It presents a novel mechanism for the dissipative creation of topological states with non-zero Chern number via short-range system-bath interactions.

Findings

Dissipative process can produce a stable Chern insulator state.

The method is feasible with cold atom optical lattice experiments.

A non-equilibrium phase diagram featuring topological phases is demonstrated.

Abstract

Engineered dissipation can be employed to prepare interesting quantum many body states in a non-equilibrium fashion. The basic idea is to obtain the state of interest as the unique steady state of a quantum master equation, irrespective of the initial state. Due to a fundamental competition of topology and locality, the dissipative preparation of gapped topological phases with a non-vanishing Chern number has so far remained elusive. Here, we study the open quantum system dynamics of fermions on a two-dimensional lattice in the framework of a Lindblad master equation. In particular, we discover a mechanism to dissipatively prepare a topological steady state with non-zero Chern number by means of short-range system bath interaction. Quite remarkably, this gives rise to a stable topological phase in a non-equilibrium phase diagram. We demonstrate how our theoretical construction can be implemented in a microscopic model that is experimentally feasible with cold atoms in optical lattices.