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arXiv · 2309.12976

Inverse-designed broadband low-loss grating coupler on thick lithium-niobate-on-insulator platform

Yijun Xie·Mingming Nie·Shu-Wei Huang
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Abstract

A grating coupler on 700-nm-thick Z-cut lithium-niobate-on-insulator platform with high coupling efficiency, large bandwidth, and high fabrication tolerance is designed and optimized by inverse design method. The optimized grating coupler is fabricated with a single set of e-beam lithography and etching process, and it is experimentally characterized to possess peak coupling efficiency of -3.8 dB at 1574.93 nm, 1-dB bandwidth of 71.7 nm, and 3-dB bandwidth of over 120 nm.

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Yijun Xie, Mingming Nie, Shu-Wei Huang. 2023-09-22. Inverse-designed broadband low-loss grating coupler on thick lithium-niobate-on-insulator platform. https://arxiv.org/abs/2309.12976

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