Inter-mode soliton linear-wave scattering in a Kerr microresonator

Soliton microresonator frequency combs (microcombs) have recently emerged as an attractive new type of optical comb source with a wide range applications proposed and demonstrated. To extend the optical bandwidth of these microresonator sources, several previous studies have proposed and studied the injection of an additional optical probe wave into the resonator. In this case, nonlinear scattering between the injected probe and the original soliton enables the formation of new comb frequencies through a phase-matched cascade of four-wave mixing processes. In thiswork, we expand the relevant analyses to consider soliton-linear wave interactions when the soliton and the probe fields propagate in different mode families. We obtain an expression for the phase-matched idler locations as a function of the dispersion of the resonator and the phase detuning of the injected probe. We confirm our theoretical predictions in experiments performed in a silica waveguide ring microresonator. (c) 2022 Optica Publishing Group

Automated summary

Soliton microresonator frequency combs are a new type of optical comb source that can be extended in optical bandwidth by injecting an optical probe wave. This study focuses on the interaction between solitons and linear waves in different mode families and derives an expression for the phase-matched idler locations based on the dispersion of the resonator and the phase detuning of the injected probe. Experimental confirmation is provided using a silica waveguide ring microresonator.