Compact polarization-independent non-volatile optical switches
Fangfa Bao, Jiakai Ruan, Weijia Li, Wei Zhang, Guoxiang Wang, Xiang Shen, Yixiao Gao
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) Sb 2 S 3 . By incorporating Sb 2 S 3 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 µm, which may find promising applications in reconfigurable photonic circuits for on-chip optical signal processing.