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arXiv · 2012.10775

Photorefraction-induced Bragg scattering in cryogenic lithium niobate ring resonators

Yuntao Xu·Ayed Al Sayem·Chang-Ling Zou·Linran Fan·Hong X. Tang
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Abstract

We report intracavity Bragg scattering induced by photorefractive (PR) effect in high-Q lithium niobate (LN) ring resonators at cryogenic temperatures. We show that, when a cavity mode is strongly excited, the PR effect imprints a long-lived periodic space-charge field. This residual field in turn creates a refractive index modulation pattern that dramatically enhances the back scattering of an incoming probe light, and results in selective and reconfigurable mode splittings. This PR-induced Bragg scattering effect, despite being undesired for many applications, could be utilized to enable optically programmable photonic components.

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Yuntao Xu, Ayed Al Sayem, Chang-Ling Zou, Linran Fan, Hong X. Tang. 2020-12-19. Photorefraction-induced Bragg scattering in cryogenic lithium niobate ring resonators. https://arxiv.org/abs/2012.10775

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