Simulating and probing many-body quantum states in waveguide-QED systems with giant atoms

TL;DR

This paper introduces a theoretical framework using waveguide-QED with giant atoms to simulate complex many-body quantum models, enabling spectrum detection and phase distinction in atomic chains.

Contribution

It presents a novel scheme for simulating the Aubry-André-Harper model and detecting phases using photon transmission in giant-atom waveguide-QED systems.

Findings

Simulated Hofstadter butterfly spectrum with high precision

Photon transmission distinguishes many-body localized and extended phases

Framework applicable to various 1D atomic chains

Abstract

Waveguide quantum electrodynamics (wQED) with giant atoms provides a distinctive opportunity to study one-dimensional (1D) coupled spin systems through its unique decoherence-free interactions. This study presents a theoretical framework for simulating the diagonal Aubry-Andr\'e-Harper (AAH) model in the context of giant-atom wQED. The proposed scheme employs photonic modes in the waveguide to not only mediate interactions between atoms but also to detect the energy spectrum of the atom array. To illustrate the effectiveness of this approach, we present a simulation of the Hofstadter butterfly spectrum with high precision. Furthermore, for an incommensurate AAH atomic chain, we demonstrate that the photon transmission spectrum can accurately distinguish between the many-body localized phase and the extended phase. The method presented here is also applicable to the simulation of other types of 1D atomic chains based on giant-atom wQED.