Broadband spectral mapping of photo-induced second-harmonic generation in silicon nitride microresonators
Abstract
By employing a pump-probe technique for enhanced spectral mapping of the dynamics in nonlinear frequency conversion, we demonstrate that photo-induced second-harmonic generation (SHG) in silicon nitride (Si3N4) microresonators can persist when transitioning from the preferred doubly resonant condition--where the resonances of the optical harmonics are required to be matched--to a highly detuned state where the generated second harmonic is significantly shifted away from its corresponding resonance. This results in an unconventionally broad conversion bandwidth. Other intriguing phenomena, such as detuning-dependent all-optical poling and nonlinear multi-mode interaction, are also presented for the first time with direct experimental evidence. Our findings provide new insights into the physics of photo-induced second-order (\chi^{(2)}) nonlinearity, highlighting its potential applications for nonlinear \chi^{(2)} photonics in integrated Si3N4 platform
Keywords
Cite
@article{arxiv.2510.05636,
title = {Broadband spectral mapping of photo-induced second-harmonic generation in silicon nitride microresonators},
author = {Ji Zhou and Marco Clementi and Samantha Sbarra and Ozan Yakar and Camille-Sophie Brès},
journal= {arXiv preprint arXiv:2510.05636},
year = {2025}
}
Comments
9 pages, 4 figures