# Tunable Topologically-protected Super- and Subradiant Boundary States in One-Dimensional Atomic Arrays

## TL;DR

This paper explores topologically protected boundary states in one-dimensional atomic arrays under a tunable magnetic field, revealing exotic band structures and edge states with potential applications in quantum sensing and imaging.

## Contribution

It introduces a novel method to realize and control topologically protected super- and subradiant states using a synthetic dimension in atomic arrays.

## Key findings

- Discovery of butterfly-like nontrivial bandstructure
- Identification of topologically-protected edge states with super/subradiance
- Potential for quantum sensing and super-resolution imaging

## Abstract

Single-photon super- and subradiance are important for the quantum memory and quantum information. We investigate one-dimensional atomic arrays under the spatially periodic magnetic field with a tunable phase, which provides a distinctive physics aspect of revealing exotic two-dimensional topological phenomena with a synthetic dimension. A butterfly-like nontrivial bandstructure associated with the non-Hermitian physics involving strong long-range interactions has been discovered. It leads to pairs of topologically-protected edge states, which exhibit the robust super- or subradiance behavior, localized at the boundaries of the atomic arrays. This work opens an avenue of exploring an interacting quantum optical platform with synthetic dimensions pointing to potential implications for quantum sensing as well as the super-resolution imaging.