Photon-photon Correlations from a Pair of Strongly Coupled Two-Level Emitters

TL;DR

This paper explores how strong coupling between two two-level emitters affects photon correlations, revealing resonance-induced correlations and breaking time-symmetry, with implications for quantum light sources.

Contribution

It introduces a spectral filtering technique to control photon statistics and analyzes both real and virtual photon emission processes in strongly coupled emitters.

Findings

Resonance-induced photon correlations are identified.

Spectral filtering manipulates light statistics effectively.

Time-symmetry of correlations is broken in the system.

Abstract

We investigate two-color photon correlations in the light emitted by strongly coupled two-level emitters. Spectral filtering allows us to manipulate the collected light statistics and we show that the resonances induced by dipole-dipole interactions give rise to specific correlations, where the time-symmetry of the correlations is broken. Based on the collective dressed states, our study encompasses both the case of real processes, where the photons are associated with specific resonances and classical correlations between each other, and virtual processes, where pairs of photons are emitted with non-classical correlations.