夹层嵌入式金属光栅偏振分束器的设计

Design of Interlayer Embedded Metal Grating Polarization Beam Splitter

为获得高性能的宽带偏振分束器,设计了夹层式金属光栅模型。应用遗传算法对光栅参数进行优化,设计出具有高消光比、宽带宽的偏振分束器。采用严格耦合波理论对其性能进行分析研究。模拟结果表明,该模型在波长范围900nm^1200nm之间,入射角-30°~30°,具有优良的偏振分束效果,衍射效率可达到95%以上。TE波反射效率和TM波透射效率最高分别可达到96.8%和97.5%,结构模型消光比高,TE波的反射消光比和TM波的透射消光比分别可达到37dB和33dB,该光栅结构简单紧凑,制作灵活且性能稳定。

In order to obtain a high performance broadband polarization beam splitter, a sandwich type met al grating model was designed. The genetic algorithm is used to optimize the grating parameters, and a po larization beam splitter with high extinction ratio and wide bandwidth is designed. Using rigorous coupled wave theory to analyze its performance. In the result, the model has an excellent polarization splitting effect in the wavelength range of 900nm 1200nm and an incident angle of 30° to 30°, and the diffraction efficiency can reach more than 95 °. The highest TE wave reflection efficiency and TM wave transmission efficiency can reach 96.8G and 97.5G, respectively. The structural model has a high extinction ratio, and the reflection extinction ratio of the TE wave and the transmission extinction ratio of the TM wave can reach 37 dB and 33 dB, respectively. The grating structure is simple, compact, flexible and stable in per formance.