Multi-color solitons and frequency combs in broadband microresonators

The three-wave equations that describe broadband microresonators with a nearly quartic dispersion are briefly derived. They are then applied to describe recent experimental results in which interleaved frequency combs are generated, from which a single broadband frequency comb can be generated under the right conditions [1,2]. 1. G. Moille, et al., “Kerr-induced synchronization of a cavity soliton to an optical reference,” Nature 624, 267–274 (14 Dec. 2023) [doi: 10.1038/s41586-023-06730-0]. 2. G. Moille, et al., “Ultra-broadband Kerr microcomb through soliton spectral translation,” Nat. Comm. 12, 7275 (2021) [doi: 10.1038/s4146-021-27469-0].