Multipartite quantum correlated bright frequency combs

TL;DR

This paper demonstrates the generation of multipartite quantum correlations in bright frequency combs from a silicon nitride microresonator, advancing integrated quantum photonics for future quantum technologies.

Contribution

It reports the first experimental observation of multipartite quantum correlations in microresonator-based frequency combs, extending beyond two-mode correlations.

Findings

Achieved noise reductions of -2.5 dB and -2 dB indicating quantum correlations.

Transition from two-mode to multipartite correlation demonstrated.

Identified a constant in the non-linear interaction Hamiltonian to assess multipartite behavior.

Abstract

This experimental work demonstrates multipartite quantum correlation in bright frequency combs out of a microresonator integrated on silicon nitride operating above its oscillation threshold. Multipartite features, going beyond so far reported two-mode correlation, naturally arise due to a cascade of non-linear optical processes, making a single-color laser pump sufficient to initiate their generation. Our results show the transition from two-mode to multipartite correlation, witnessed by noise reductions as low as $-2.5$\,dB and $-2$\,dB, respectively, compared to corresponding classical levels. A constant of the movement of the non-linear interaction Hamiltonian is identified and used to asses the multipartite behavior. Reported demonstrations pave the way to next generation on-chip multipartite sources for quantum technologies applications.