A switchable polarization beam splitter utilizing GST-on-silicon waveguides is introduced and comprehensively investigated in this paper. Based on the phase matching and mode hybridization, structural parameters of the presented device are optimized by using the particle swarm optimization algorithm and finite difference time domain method, so that the output fundamental transverse-electric (TE0) and transverse-magnetic (TM0) modes can be switched by controlling the phase state of GST and the device exhibits broad bandwidth, low crosstalk, and high polarization extinction ratio. For the designed device with the amorphous GST, the crosstalk is lower than −23.40 dB and the polarization extinction ratio is larger than 21.35 dB over the C-band. In the case of the crystalline GST, within the C-band, the crosstalk of less than −27.37 dB and the polarization extinction ratio of greater than 21.37 dB are achieved.

中文翻译：

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基于 GST-on-silicon 波导的可切换偏振分束器

本文介绍并全面研究了一种利用 GS​​T-on-silicon 波导的可切换偏振分束器。基于相位匹配和模式杂化，利用粒子群优化算法和有限差分时域方法对所提出装置的结构参数进行优化，使输出基本横电（TE0）和横磁（TM0）模式可以通过控制 GST 的相位状态进行切换，并且该器件具有宽带宽、低串扰和高偏振消光比。对于具有非晶 GST 的设计器件，串扰低于 -23.40 dB，并且在 C 波段上的极化消光比大于 21.35 dB。在晶体 GST 的情况下，在 C 波段内，串扰小于 -27。