# Optical waveguiding by atomic entanglement in multilevel atom arrays

## TL;DR

This paper demonstrates that atomic entanglement in multilevel atom arrays can enable optical waveguiding, revealing collective quantum effects that persist beyond simple atomic models and advancing understanding of realistic quantum emitter systems.

## Contribution

It shows that waveguiding arises from atomic entanglement in multilevel arrays, extending previous models to more realistic atomic structures with hyperfine levels.

## Key findings

- Waveguiding can result from atomic entanglement in multilevel atom arrays.
- Necessary conditions for waveguiding involve specific entanglement and atomic structure.
- The work advances understanding of collective effects in realistic atomic systems.

## Abstract

The optical properties of sub-wavelength arrays of atoms or other quantum emitters have attracted significant interest recently. For example, the strong constructive or destructive interference of emitted light enables arrays to function as nearly perfect mirrors, support topological edge states, and allow for exponentially better quantum memories. In these proposals, the assumed atomic structure was simple, consisting of a unique electronic ground state. Within linear optics, the system is then equivalent to a periodic array of classical dielectric particles, whose periodicity supports the emergence of guided modes. However, it has not been known whether such phenomena persist in the presence of hyperfine structure, as exhibited by most quantum emitters. Here, we show that waveguiding can arise from rich atomic entanglement as a quantum many-body effect, and elucidate the necessary conditions. Our work represents a significant step forward in understanding collective effects in arrays of atoms with realistic electronic structure.