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arXiv · 2404.04266

WGMR Self-Injection Locking Method Based on Enhanced Optical Feedback with Auxiliary Prism

Jiajun Wu·Shan Zhong·Songbai Kang
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Abstract

The optical feedback intensity is an important parameter for realizing narrow linewidth lasers in Whispering-gallery-mode resonator (WGMR) self-injection locking technology. We proposed an approach that enhances the intensity of intracavity feedback in crystalline WGMR by using only a single coated auxiliary prism. Compared to the Rayleigh scattering, the feedback intensity of the enhanced scheme increased by more than a hundred times. Furthermore, we demonstrated that, with the enhanced approach, the instantaneous linewidth of the laser was suppressed to 7 Hz level, the locking range was expanded up to 8 GHz, and the relative intensity noise (RIN) was reduced to -152 dBc/Hz@10MHz. The feedback enhanced design is compact, easy-to-operated and can be integrated with the WGMR. It provides a miniaturized solution for controlling optical feedback intensity in WGMR self-injection locking technology.

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Jiajun Wu, Shan Zhong, Songbai Kang. 2024-03-19. WGMR Self-Injection Locking Method Based on Enhanced Optical Feedback with Auxiliary Prism. https://arxiv.org/abs/2404.04266

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