Polaron-Polaritons in Subwavelength Arrays of Trapped Atoms

TL;DR

This paper explores how lattice deformations in subwavelength atomic arrays create hybrid quasiparticles called polaron-polaritons, affecting light-matter interactions, decay, and transport properties, with implications for quantum optics applications.

Contribution

It introduces the concept of polaron-polaritons in atomic arrays and analyzes their effects on decay, excitation, and reflectivity using analytical and numerical methods.

Findings

Phonons can enhance decay of subradiant states.

Dark excitation transport remains robust at low trap frequencies.

Motion reduces mirror reflectivity but can be mitigated.

Abstract

Subwavelength arrays of atoms trapped in optical lattices or tweezers are inherently susceptible to deformations: Optomechanical forces produce lattice distortions, which, in turn, modify the optical response of the array. We show that this coupling hybridizes collective atomic excitations (polaritons) with phonons, forming polaron-polaritons -- the fundamental quasiparticles governing light-matter interactions in arrays of trapped atoms. Using analytical polaron theory and numerical simulations, we show that: (1) phonons can strongly enhance the decay of subradiant states, but also enable their efficient excitation; (2) transport of dark excitations remains remarkably robust even at low trap frequencies, except when a polariton can resonantly scatter phonons; and (3) motion reduces the reflectivity of a two-dimensional atomic mirror, however, we identify mechanisms that mitigate this degradation and restore reflectivity above 99% in some cases. Our findings lay the foundation for analyzing motional effects in key applications and suggest new ways to harness them in state-of-the-art experiments.