Fano effect induced giant and robust enhancement of photon correlations in cavity QED systems

TL;DR

This paper demonstrates that the Fano effect can significantly enhance photon correlations in cavity QED systems, even under weak coupling, by tuning interference between dissipation channels, leading to more robust nonclassical light generation.

Contribution

It provides an analytical framework showing how Fano interference improves photon antibunching and robustness against decoherence in atom-cavity systems, expanding possibilities for nonclassical light sources.

Findings

Fano effect can enhance photon antibunching by over four orders of magnitude.

The enhancement is related to the Fano parameter q.

Fano-induced photon correlations are robust against decoherence and weak coupling.

Abstract

Fano effect arising from interference between two dissipation channels to the radiation continuum enables to tune the photon statistics. Understanding the role of Fano effect and exploiting to achieve strong photon correlations are of both fundamental and applied significance. We present an analytical description of Fano-enhanced photon correlations based on cavity quantum electrodynamics to show that, the Fano effect in atom-cavity systems can improve the degree of antibunching by over four orders of magnitude. The enhancement factors and the optimal conditions are explicitly given, and found related to the Fano parameter $q$. Remarkably, the Fano enhancement manifests robustness against the decoherence processes, and can survive in the weak coupling regime. We expect our work to provide insight in tuning the photon statistics through Fano effect, which offers a new route to enhance the photon correlations, as well as the possibility of generating nonclassical light in a wider diversity of systems without the need of strong light-matter interaction.