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arXiv · 2510.08170

Proposal for Forward Brillouin Inter-Modal Scattering in Non-suspended Lithium Niobate Waveguides at Visible Wavelengths

Jia-Lin Chen·Yuan-Hao Yang·Zheng-Xu Zhu·Jia-Qi Wang·Xin-Biao Xu·Ming Li·Zheng-Fu Han·Guang-Can Guo·Wei Chen·Chang-Ling Zou
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Abstract

Thin-film lithium niobate on sapphire provides an excellent platform for simultaneously confining acoustic and optical modes without suspended structures, enabling efficient acousto-optic modulation through strong piezoelectric coupling. Here, we identify the challenges in realizing the forward Brillouin interaction at visible wavelengths, and overcome the limitation by introducing a quasi-phase-matching scheme through periodic waveguide width modulation. We predict a complete inter-modal optical conversion over 1.1 mm using only 1 mW acoustic power. Our study paves the way for high-performance visible-wavelength acousto-optic devices on integrated platforms.

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Jia-Lin Chen, Yuan-Hao Yang, Zheng-Xu Zhu, Jia-Qi Wang, Xin-Biao Xu, Ming Li, Zheng-Fu Han, Guang-Can Guo, Wei Chen, Chang-Ling Zou. 2025-10-09. Proposal for Forward Brillouin Inter-Modal Scattering in Non-suspended Lithium Niobate Waveguides at Visible Wavelengths. https://arxiv.org/abs/2510.08170

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