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arXiv · 2311.13965

Efficient light couplers to topological slow light waveguides in valley photonic crystals

Hironobu Yoshimi·Takuto Yamaguchi·Satomi Ishida·Yasutomo Ota·Satoshi Iwamoto
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Abstract

We numerically and experimentally demonstrate efficient light couplers between topological slow light waveguides in valley photonic crystals (VPhCs) and wire waveguides. By numerical simulations, we obtained a high coupling efficiency of -0.84 dB/coupler on average in the slow light regime of a group index ng = 10 - 30. Experimentally, we fabricated the couplers in a Si slab and measured the transmitted power of the devices. We realized a high coupling efficiency of approximately -1.2 dB/coupler in the slow light region of ng = 10 - 30, which is close to the result from the numerical simulations. These demonstrations will lay the groundwork for low-loss photonic integrated circuits using topological slow light waveguides.

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Hironobu Yoshimi, Takuto Yamaguchi, Satomi Ishida, Yasutomo Ota, Satoshi Iwamoto. 2023-11-23. Efficient light couplers to topological slow light waveguides in valley photonic crystals. https://arxiv.org/abs/2311.13965

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