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arXiv · 2312.10640

Inverse design of coherent supercontinuum generation using free-form nanophotonic waveguides

Chia-Yi Lee·Yanwu Liu·Yinke Cheng·Cheng-Hao Lao·Qihuang Gong·Qi-Fan Yang
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Abstract

Many key functionalities of optical frequency combs such as self-referencing and broad spectral access rely on coherent supercontinuum generation (SCG). While nanophotonic waveguides have emerged as a compact and power-efficient platform for SCG, their geometric degrees of freedom have not been fully utilized due to the underlying nonlinear and stochastic physics. Here, we introduce inverse design to unlock free-form waveguides for coherent SCG. The efficacy of our design is numerically and experimentally demonstrated on Si3N4 waveguides, producing flat and coherent spectra from visible to mid-infrared wavelengths. Our work has direct applications in developing chip-based broadband light sources for spectroscopy, metrology, and sensing across multiple spectral regimes.

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Chia-Yi Lee, Yanwu Liu, Yinke Cheng, Cheng-Hao Lao, Qihuang Gong, Qi-Fan Yang. 2023-12-17. Inverse design of coherent supercontinuum generation using free-form nanophotonic waveguides. https://arxiv.org/abs/2312.10640

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