Simulating Z_2 topological insulators with cold atoms in a one-dimensional optical lattice

TL;DR

This paper proposes a method to simulate and detect Z2 topological insulators using cold atoms in a one-dimensional optical lattice, enabling controlled study of topological phases and edge states.

Contribution

It introduces a novel experimental scheme employing a 1D Aubry-Andre model with SU(2) gauge structure to emulate 2D topological insulators with cold atoms.

Findings

Demonstrates adiabatic pumping of spin-polarized edge states.

Proposes density measurements as signatures of topological phases.

Shows controllable transfer of topologically protected states.

Abstract

We propose an experimental scheme to simulate and detect the properties of time-reversal invariant topological insulators, using cold atoms trapped in one-dimensional bichromatic optical lattices. This system is described by a one-dimensional Aubry-Andre model with an additional SU(2) gauge structure, which captures the essential properties of a two-dimensional Z2 topological insulator. We demonstrate that topologically protected edge states, with opposite spin orientations, can be pumped across the lattice by sweeping a laser phase adiabatically. This process constitutes an elegant way to transfer topologically protected quantum states in a highly controllable environment. We discuss how density measurements could provide clear signatures of the topological phases emanating from our one-dimensional system.