Multipartite Entanglement in Bright Frequency Combs from Microresonators

TL;DR

This paper presents a theoretical model demonstrating how bright frequency combs generated in microresonators exhibit multipartite entanglement through cascaded four-wave mixing, with potential applications in quantum information processing.

Contribution

The paper introduces a general theoretical framework for analyzing multimode quantum correlations and entanglement in microresonator-generated frequency combs, extending understanding beyond bipartite regimes.

Findings

Entanglement emerges from cascading four-wave mixing processes.

Transition from bipartite to multipartite entanglement with increasing pump power.

Model applicable to various nonlinear $ ext{chi}^{(3)}$ cavities.

Abstract

We present a theoretical model of multimode quantum correlations in bright frequency combs generated in continuous-wave regime by microresonators above threshold. Our analysis shows how these correlations emerge from cascading four-wave mixing processes fed by the input pump as well as the generated bright beams. Logarithmic negativity criterion is employed to quantify entanglement between partitions of modes, demonstrating the transition from a bipartite regime just above the oscillation threshold to the multipartite one at higher input pump powers. Due to its generality, our model can be safely used to describe other kinds of non-linear $\chi$ (3) cavities.