Many-Body Quantum Optics in a Bose-Hubbard Waveguide

TL;DR

This paper investigates how many-body quantum states of photons in a Bose-Hubbard waveguide influence the collective behavior of quantum emitters, revealing new regimes of superradiance and mediated interactions.

Contribution

It introduces a model of quantum emitters coupled to a Bose-Hubbard waveguide, analyzing how photon-photon interactions affect emitter dynamics in different many-body phases.

Findings

Photon-photon interactions can trigger superradiant bursts independently of emitter spacing.

Delocalized superfluid excitations lead to distance-independent emitter couplings.

Mott-insulator quasiparticles mediate short-range interactions via doublons and holons.

Abstract

Waveguide quantum electrodynamics (QED) studies the interaction between quantum emitters and guided photons in one-dimension. When the waveguide hosts interacting photons, it becomes a platform to explore many-body quantum optics. However, the influence of photonic correlations on emitter dynamics remains poorly understood. In this work, we study the collective decay and coherent interactions of quantum emitters coupled to a one-dimensional Bose-Hubbard waveguide, an array of coupled photonic modes with repulsive on-site interactions that supports superfluid and Mott insulating phases. We show that photon-photon interactions alone can trigger a superradiant burst, independent of emitter spacing and transition frequency. In the off-resonant regime, emitters exhibit two distinct types of mediated interactions: delocalized superfluid excitations yield distance-independent couplings, while Mott-insulator quasiparticles generate short-range interactions mediated by doublons and holons. Our work bridges many-body physics and waveguide QED, revealing how photonic many-body states shape emitter dynamics.