Open AccessThird-harmonic-assisted four-wave mixing in a chip-based microresonator frequency comb generation
Author(s) -
Hao Zhang,
Yunqiu Wu,
Huan Yang,
Zongxin Ju,
Zhe Kang,
Jijun He,
Shilong Pan
Publication year - 2022
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.473472
Subject(s) - frequency comb , optics , dispersion (optics) , physics , four wave mixing , nonlinear optics , mixing (physics) , high harmonic generation , sum frequency generation , harmonic , terahertz radiation , coupling (piping) , photonics , second harmonic generation , optoelectronics , laser , materials science , acoustics , quantum mechanics , metallurgy
Microcombs generated in photonic integrated circuits can provide broadband and coherent optical frequency combs with a high repetition rate from microwave to terahertz. Coherent microcombs formed in normal group velocity dispersion microresonators usually have a flat-top temporal profile, called platicon. Here, we propose a novel scheme to generate platicon in Si 3 N 4 microresonator with the assistance of third-harmonic generation. The nonlinear coupling between the fundamental and the third-harmonic waves that draws support from third-order sum/difference frequency generation provides a new mechanism to achieve the phase matching of four-wave mixing in normal dispersion microresonators. We show that single or multiple platicons can be obtained by changing the third-harmonic nonlinear coupling strength and phase matching condition for third-order sum/difference frequency generation. Our work provides a promising solution to facilitate coherent and visible microcomb generation in a pure χ (3) microresonator, which is potential for self-referencing combs and optical clock stabilization.