A spin pump characterized by entanglement Chern numbers

TL;DR

This paper introduces a new topological invariant called the entanglement Chern number to characterize a spin pump in a Rice--Mele ladder model, revealing two distinct phases that can be experimentally observed in cold atom systems.

Contribution

The paper proposes the entanglement Chern number as a novel topological measure for many-body ground states in spin pumps, expanding the understanding of topological phases.

Findings

The model exhibits two phases distinguished by different entanglement Chern numbers.

The entanglement Chern number effectively characterizes the topological nature of the spin pump.

Experimental verification is feasible using cold atom setups.

Abstract

We study a spin pump on a two-leg ladder chain of the Rice--Mele model. To characterize the spin pump, we propose the Chern number for the many-body ground state of the entanglement Hamiltonian, which is referred to as the entanglement Chern number. We show that this model has two phases distinguished by the entanglement Chern numbers. These two phases can be experimentally verified in cold atoms.