论文标题
光空间差异和悬浮的亚波长期光栅
Optical spatial differentiation with suspended subwavelength gratings
论文作者
论文摘要
我们使用薄悬浮的亚波长光栅展示了光束横向轮廓的一阶和二阶空间分化。使用电子束光刻和等离子体蚀刻的悬挂式200 nm厚的氮化膜悬挂式氮化硅膜上对高度反射的一维光栅进行图案图案。这些光栅的光传递是在正常和倾斜的发生率下进行实验测量的，该光栅是用TM或TE极化光进行照明的，发现与分析耦合模式模型的预测以及严格的耦合波浪分析数值模拟非常吻合。高质量的高质量和二阶空间分化在倾斜和正常入射率时分别在传播中观察到高斯束的高质量分化。这种易于制作的超薄和无损耗的光学组件可能对光束塑形和光学信息处理和计算具有吸引力。
We demonstrate first- and second-order spatial differentiation of an optical beam transverse profile using thin suspended subwavelength gratings. Highly reflective one-dimensional gratings are patterned on suspended 200 nm-thick silicon nitride membranes using Electron Beam Lithography and plasma etching. The optical transmission of these gratings, designed for illumination with either TM or TE polarized light, are experimentally measured under normal and oblique incidence and found to be in excellent agreement with the predictions of an analytical coupled-mode model as well as Rigorous Coupled Wave Analysis numerical simulations. High quality first- and second-order spatial differentiation of a Gaussian beam are observed in transmission at oblique and normal incidence, respectively. Such easy-to-fabricate, ultrathin and loss-free optical components may be attractive for beam shaping and optical information processing and computing.
