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arXiv · 2306.10660

High-coherence hybrid-integrated 780 nm source by self-injection-locked second-harmonic generation in a high-Q silicon-nitride resonator

Bohan Li·Zhiquan Yuan·Warren Jin·Lue Wu·Joel Guo·Qing-Xin Ji·Avi Feshali·Mario Paniccia·John E. Bowers·Kerry J. Vahala
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Abstract

By self-injection-locking a 1560 nm distributed feedback semiconductor laser to a high-$Q$ silicon nitride resonator, a high-coherence 780 nm second harmonic signal is generated via the photogalvanic-induced second-order nonlinearity. A record-low frequency noise floor of 4 Hz$^2$/Hz is achieved for the 780 nm emission. The approach can be generalized for signal generation over a wide range of visible and near-visible bands.

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Bohan Li, Zhiquan Yuan, Warren Jin, Lue Wu, Joel Guo, Qing-Xin Ji, Avi Feshali, Mario Paniccia, John E. Bowers, Kerry J. Vahala. 2023-06-19. High-coherence hybrid-integrated 780 nm source by self-injection-locked second-harmonic generation in a high-Q silicon-nitride resonator. https://arxiv.org/abs/2306.10660

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