摘要：A design of polarization-maintaining retro-reflectors （PMRRs） for folded-path applications is proposed and analyzed. The prism-based scheme enables the output light, which is parallel to the input, to have an identical state of polarization. The principle of the design is theoretically verified, and the related error is analyzed due to possible manufacturing imperfection. The maximum spatial angle error is ±2.75°. The effect on the extinction ratio and insertion loss is also discussed, which further proves the design＇s feasibility in practical applications.

摘要：单极势垒异质结构可以选择性地降低暗电流,但不影响光电流,是一种构建高性能光电探测器的有效策略.特别地,具有可调谐能带结构和自钝化表面的二维(2D)材料不仅能满足能带匹配要求,而且避免了界面缺陷和晶格失配,有助于设计单极势垒异质结构.这里,我们展示了一种混合维度WS_(2)/WSe_(2)/p-Si单极势垒异质结光电探测器.其中,2D WS_(2)充当光子吸收体,原子级厚度的WSe_(2)充当单极势垒,3D p-Si充当光生载流子收集器.插入的WSe_(2)不仅减轻了有害的衬底效应,而且形成了高导带势垒,可以过滤掉若干暗电流分量,同时不影响光电流.在隧穿效应和载流子倍增效应的驱动下,该WS_(2)/WSe_(2)/p-Si器件表现出高于10~5的高开/关比、2.39×10^(12)Jones的高探测度和8.47/7.98毫秒的快速上升/衰减时间.这些优点显著优于传统的WS_(2)/p-Si器件,为设计高性能的光电器件开辟了一个新方案.