Abstract This paper presents a compact dual-mode polarization beam splitter (PBS) based on silicon on insulator platform. The proposed PBS separates two lowest-order transverse magnetic (TM) modes from two lowest-order transverse electric (TE) ones by employing an optimized tapered directional coupler. To the best of our knowledge, this is the first PBS with the ability of separating two sets of modes with different polarizations, simultaneously. Such a component is an essential block in the hybrid mode/polarization-multiplexing systems. The three-dimensional finite-difference time-domain (FDTD) simulation results confirm that the designed PBS has a low loss of 1.6 dB and high extinction ratio of more than 10 dB over a broad wavelength range of 90 nm. Also, the presented PBS tolerates ± 15 nm change in the coupling gap, ± 30 nm waveguide width deflection, and more than ± 100 nm coupling length variation with an insertion loss lower than 1 dB and extinction ratio higher than 10 dB.

中文翻译：

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用于混合模式/偏振分复用系统的硅基双模偏振分束器

摘要 本文提出了一种基于绝缘体上硅平台的紧凑型双模偏振分束器（PBS）。所提出的 PBS 通过采用优化的锥形定向耦合器将两个最低阶横向磁 (TM) 模式与两个最低阶横向电 (TE) 模式分开。据我们所知，这是第一个能够同时分离两组不同偏振模式的 PBS。这种组件是混合模式/极化复用系统中的基本模块。三维时域有限差分 (FDTD) 仿真结果证实，所设计的 PBS 在 90 nm 的宽波长范围内具有 1.6 dB 的低损耗和超过 10 dB 的高消光比。此外，所提出的 PBS 容许耦合间隙的 ± 15 nm 变化，