We present the design and experimental results of a novel polarization beam splitter (PBS) with a high polarization extinction ratio (PER) made on a Si₃N₄ platform. The PBS is composed of two identical polarization-independent multi-mode interferometers and two identical apodized Bragg gratings. The operating principle of this device is based on the fact that the TE and TM stopbands of the grating are centered at different wavelengths. The reflected and transmitted light from the gratings are routed to separate output ports by the two-MMI configuration. The experimental results show that a PER of > 30 dB is achieved over a bandwidth of 22 nm, with an insertion loss of ∼ 1.1 dB. The total length of the device is ∼ 820 µm.

中文翻译：

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基于偏振无关的MMI和切趾布拉格光栅的氮化硅偏振分束器

我们介绍了在Si ₃ N ₄平台上制造的具有高偏振消光比（PER）的新型偏振分束器（PBS）的设计和实验结果。PBS由两个相同的偏振无关多模干涉仪和两个相同的切趾布拉格光栅组成。该设备的工作原理基于这样一个事实，即光栅的TE和TM阻带位于不同波长的中心。来自光栅的反射和透射光通过2 MMI配置路由到单独的输出端口。实验结果表明，在22 nm带宽上，PER大于30 dB，插入损耗约为1.1 dB。装置的总长度约为820 µm。