Engineering Atom-Photon Hybridization with Density-Modulated Atomic Ensembles in Coupled Cavities

TL;DR

This paper demonstrates how spatially engineered atomic ensembles in coupled cavities can control atom-photon interactions, enabling selective photon transfer and tunable many-body effects.

Contribution

It introduces a method to manipulate mode couplings via spatial structure of atomic ensembles, advancing control over hybrid light-matter systems.

Findings

Homogeneous clouds suppress mode-mode couplings through destructive interference.

Grated clouds can preserve mode couplings under Bragg conditions.

Spatial engineering enables selective photon transfer and control of many-body complexity.

Abstract

Radiation-matter hybridization allows atoms to serve as mediators of effective interactions between light modes and, conversely, to interact among themselves via light. Here we exploit the spatial structure of atomic ensembles to control the coupling between modes of distinct cavities, thereby reshaping the resulting atom-photon spectra. We show that extended homogeneous clouds suppress mode-mode couplings through destructive interference, whereas grated clouds can preserve them under specific Bragg conditions. This leads to mode-mode spectral subsplittings, where collectivity arises not only from the atom number but also from the ability to tune modes of different cavities independently. Our results establish spatially engineered atomic ensembles as a pathway to selective photon transfer between modes and precise control of many-body complexity.