Yuan Zhiquan, Ge Jinhao, Liu Peng, Li Bohan, Li Mingxiao, Liu Jin-Yu, Yu Yan, Chen Hao-Jing, Bowers John, Vahala Kerry
T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA 91125, USA.
ECE Department, University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
Sci Adv. 2025 Jul 4;11(27):eadw2781. doi: 10.1126/sciadv.adw2781. Epub 2025 Jul 2.
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- SiN microresonator. On-chip green power as high as 5.3 milliwatts is generated with a conversion efficiency of 141% per watt (absolute 7.9%). A space-charge grating induced by the photogalvanic effect realizes reconfigurable grating numbers and flexible wavelength tuning over a range of 2.6 terahertz. In addition, grating formation dynamics and competition are observed. These findings underscore the potential of SiN as a robust, integrative platform for on-chip, tunable green light sources.
实现紧凑且高效的可见激光源对于广泛的应用至关重要。然而，传统半导体激光技术在产生高亮度绿光方面面临困难，在波长覆盖上留下了一个“绿色缺口”。二次谐波产生（SHG）通过将近红外源高效且光谱纯地转换为可见波长提供了一种有前景的替代方案。在此，我们展示了使用高硅氮微谐振器在绿色光谱范围内实现高效且可调谐的SHG。产生了高达5.3毫瓦的片上绿色功率，每瓦转换效率为141%（绝对7.9%）。由光电流效应诱导的空间电荷光栅实现了可重构的光栅数量以及在2.6太赫兹范围内的灵活波长调谐。此外，还观察到了光栅形成动力学和竞争。这些发现强调了硅氮作为用于片上可调谐绿色光源的强大集成平台的潜力。
