Silicon polarization beam splitter based on cascaded multimode anti-symmetric apodized Bragg gratings for 1.55 and 2 μm wavebands

作者：Liang Zhang, Guanglian Cheng, Qiyuan Yi, Zengfan Shen, Zhiwei Yan, Qiyuan Li, Xinzhe Xiong, Shuang Zheng, Shuai Cui, Yuan Yu, Yi Zou, Chaotan Sima, Li Shen · 发表于：Optics Letters · 年份：2025 · DOI：10.1364/ol.558025 · 被引用次数：4 · 研究领域：Photonic and Optical Devices、Advanced Fiber Laser Technologies、Advanced Fiber Optic Sensors

Silicon polarization beam splitters (PBS) have garnered significant interest for on-chip polarization management in optical communications and quantum applications. However, maintaining polarization extinction across disparate wavebands remains challenging, and very few on-chip polarization-handling devices can operate with ultrabroad bandwidths or in multi-wave band. Here, we present a novel PBS that can achieve an unprecedented dual-band operation with ultrahigh polarization extinction ratios (PER). The dual-band PBS function is achieved using a dual-band TE 0 /TE 1 mode (de)multiplexer and cascaded multimode anti-symmetric apodized Bragg gratings (MASABGs). The MASABG allows for strong coupling between the TE 0 and the TE 1 modes. For the fabricated device, the measured bandwidths (BWs) for PER > 20 dB are ∼115 nm for the 1.55-μm band and ∼100 nm for the 2-μm band, respectively. Additionally, the measured ILs are 0.5/1.2 dB at 1550 nm and 3.1/1.1 dB at 2000 nm for TE/TM polarizations.