Modeling of dual frequency combs and bistable solitons in third-harmonic generation

TL;DR

This paper presents a theoretical model for dual-frequency combs in a nonlinear cavity system, revealing conditions for bistable solitons and potential applications in optical clocks and sensing.

Contribution

It introduces a mean-field model for dual-comb generation with phase-matching in a $ ext{chi}^{(3)}$ cavity, highlighting bistable solitons and broad spectral access.

Findings

Conditions for multistable cavity solitons identified

Bistable solitons coexist at same pump parameters

Third-harmonic combs enable access to multiple spectral regions

Abstract

Phase-matching of the third-harmonic generation process can be used to extend the emission of radiation from Kerr microresonators into new spectral regions far from the pump wavelength. Here, we present a theoretical mean-field model for optical frequency combs in a dissipative and nonlinear $\chi^{(3)}$-based cavity system with parametric coupling between fundamental and third-harmonic waves. We investigate temporally dispersive dual-comb generation of phase-matched combs with broad bandwidth, and report conditions for accessing a multistable regime that simultaneously supports two types of coupled bright cavity solitons. These bistable cavity solitons coexist for the same pump power and frequency detuning, while featuring dissimilar amplitudes of their individual field components. Third-harmonic generation frequency combs can permit telecom pump laser sources to simultaneously directly access both the near-infrared and the visible regions, which may be advantageous for the development of optical clocks and sensing applications.