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Title: Photorefraction-induced Bragg scattering in cryogenic lithium niobate ring resonators

We report intracavity Bragg scattering induced by the photorefractive (PR) effect in high-Qlithium niobate 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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Author(s) / Creator(s):
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Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Letters
0146-9592; OPLEDP
Page Range / eLocation ID:
Article No. 432
Medium: X
Sponsoring Org:
National Science Foundation
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