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arXiv · 2508.20490

Compact polarization-independent non-volatile optical switches

Fangfa Bao·Jiakai Ruan·Weijia Li·Wei Zhang·Guoxiang Wang·Xiang Shen·Yixiao Gao
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Abstract

Compact, non-volatile optical switches on silicon platforms are essential for reconfigurable photonics, but the strong anisotropy of silicon waveguides leads to polarization-dependent performance. In this paper, we propose a polarization-independent, non-volatile optical switch utilizing low-loss phase change material (PCM) Sb2S3. By incorporating Sb2S3 into a multimode slot waveguide, multimode interference can be efficiently tuned for both TE and TM polarizations, owing to enhanced light-PCM interaction. Polarization-independent switching is achieved through the optimal design of the multimode slot waveguide region. The proposed non-volatile switch demonstrates a crosstalk (CT) < -21.9 dB and insertion loss (IL) < 0.12 dB at 1550 nm with a multimode section length of 9.67 {\mu}m, which may find promising applications in reconfigurable photonic circuits for on-chip optical signal processing.

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Fangfa Bao, Jiakai Ruan, Weijia Li, Wei Zhang, Guoxiang Wang, Xiang Shen, Yixiao Gao. 2025-08-28. Compact polarization-independent non-volatile optical switches. https://arxiv.org/abs/2508.20490

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