Efficient and wavelength-tunable second-harmonic generation towards the green gap
Abstract
Achieving compact and efficient visible laser sources is crucial for a wide range of applications. However traditional semiconductor laser technology faces difficulties in producing high-brightness green light, leaving a green gap in wavelength coverage. Second-harmonic generation (SHG) offers a promising alternative by converting near-infrared sources to visible wavelengths with high efficiency and spectral purity. Here, we demonstrate efficient and tunable SHG within the green spectrum using a high-Q Si3N4 microresonator. A space-charge grating induced by the photogalvanic effect realizes reconfigurable grating numbers and flexible wavelength tuning. Additionally, grating formation dynamics and competition is observed. These findings underscore the potential of silicon nitride as a robust, integrative platform for on-chip, tunable green light sources.
Cite
@article{arxiv.2504.17869,
title = {Efficient and wavelength-tunable second-harmonic generation towards the green gap},
author = {Zhiquan Yuan and Jinhao Ge and Peng Liu and Bohan Li and Mingxiao Li and Jin-Yu Liu and Yan Yu and Hao-Jing Chen and John Bowers and Kerry Vahala},
journal= {arXiv preprint arXiv:2504.17869},
year = {2025}
}