亚波长光栅偏振分束器的研究  

Research on Sub-Wavelength Grating Polarizing Beam Splitter

作　　者：郭楚才[1] 叶卫民[1] 袁晓东[1] 曾淳[1] 季家镕[1] 

机构地区：[1]国防科学技术大学光电科学与工程学院,湖南长沙410073

出　　处：《光学学报》2010年第9期2690-2695,共6页Acta Optica Sinica

摘　　要：利用单层亚波长硅光栅结构设计出工作在近红外波段的偏振分束器。该偏振分束器在45°入射角附近对TE偏振光具有很高的反射率同时对TM偏振光具有很高的透射率,其设计原理是基于亚波长光栅的泄漏模共振效应以及类布儒斯特效应。利用散射矩阵方法和时域有限差分方法对偏振分束器进行设计和分析。模拟结果显示,该偏振分束器在1390～1600nm的波长范围内的反射与透射消光比大于100;同时该偏振分束器具有相对较大的入射角度容差,在有限尺寸高斯光束入射下能保持很好的性能。A near-infrared （NIR） polarizing beam splitter is designed based on a single layer sub-wavelength silicon grating,which is reflective for TE polarization and transparent for TM polarization around the incident angle of 45°. The design of the proposed beam splitter is based on the leaky-mode resonance effect and Brewster-like effect of the sub-wavelength grating. Scattering matrix method and finite-difference time-domain method are utilized to design and analyse the structure. Simulation results show that both the reflection and transmission extinction ratios of the beam splitter are over 100 in the wavelength range of 1390-1600 nm. Moreover,the polarizing beam splitter has a relative big angular tolerance and the efficiency of the beam splitter under the illumination of a Gaussian beam with finite size is very high.

关 键 词：光栅 偏振分束器 散射矩阵方法 亚波长光栅 泄漏模共振效应 类布儒斯特效应 

分 类 号：O436[机械工程—光学工程]