Enhanced generation of non-degenerate photon-pairs in nonlinear metasurfaces

TL;DR

This paper introduces a new regime for generating non-degenerate photon pairs in nonlinear metasurfaces, leveraging bound states in the continuum to significantly enhance photon rates and spectral brightness, with tunable entanglement via pump polarization.

Contribution

It demonstrates a novel photon-pair generation mechanism based on the hyperbolic topology of phase-matching in nonlinear metasurfaces, enabling enhanced and tunable quantum light sources.

Findings

Orders-of-magnitude increase in photon rate and spectral brightness.

Photon entanglement can be tuned by pump polarization.

New regime driven by bound states in the continuum resonances.

Abstract

We reveal a novel regime of photon-pair generation driven by the interplay of multiple bound states in the continuum resonances in nonlinear metasurfaces. This non-degenerate photon-pair generation is derived from the hyperbolic topology of the transverse phase-matching and can enable orders-of-magnitude enhancement of the photon rate and spectral brightness, as compared to the degenerate regime. We show that the entanglement of the photon-pairs can be tuned by varying the pump polarization, which can underpin future advances and applications of ultra-compact quantum light sources.