# Topological Quantum Optics in Two-Dimensional Atomic Arrays

## TL;DR

This paper shows that 2D atomic arrays can host topologically protected quantum optical states with robust photon transport and suppressed losses, enabling exploration of interacting topological quantum systems.

## Contribution

It introduces a novel platform of 2D atomic arrays with topologically non-trivial photonic bands and protected edge states, advancing quantum optics and topological physics.

## Key findings

- Photon propagation is robust against imperfections.
- Losses due to free space emission are suppressed.
- Topologically protected edge states are demonstrated.

## Abstract

We demonstrate that two-dimensional atomic emitter arrays with subwavelength spacing constitute topologically protected quantum optical systems where the photon propagation is robust against large imperfections while losses associated with free space emission are strongly suppressed. Breaking time-reversal symmetry with a magnetic field results in gapped photonic bands with non-trivial Chern numbers and topologically protected, long-lived edge states. Due to the inherent nonlinearity of constituent emitters, such systems provide a platform for exploring quantum optical analogues of interacting topological systems.