Squeezing enhancement through resonant interference in multiring resonators
Phys. Rev. A 114, 043735 – Published 26 October, 2026
DOI: https://doi.org/10.1103/zd75-m4bn
Abstract
We develop a nonperturbative description of squeezed light generation in an arbitrary lossy structure consisting of multiple coupled microring resonators. This is applied to two-ring photonic molecules where the interference of the fields in the coupled rings leads to a modification in the resonance spectrum near a shared resonance. Considering a dual-pump degenerate squeezing scheme under a five-resonance approximation, we investigate two methods to suppress parasitic four-wave mixing contributions and compensate for group-velocity dispersion within a primary resonator through hybridization effects with a second auxiliary resonator. In the former case, this comes from an effective splitting of the unwanted resonances supporting parasitic four-wave mixing interactions that add thermal noise to the desired degenerate squeezed state. For sufficiently strong coupling between the resonators, we demonstrate near-complete suppression of such parasitic processes, resulting in near-unit fidelities with the corresponding output state that would arise were the parasitic interactions neglected. In the latter case, the hybridization effectively shifts a pump resonance, realigning the desired dual-pump four-wave mixing process and leading to a significant enhancement of the signal generation and output squeezing.
