非对称边界的亚波长金光栅反射相位调制  

Reflection Phase Modulation of Subwavelength Gold Gratings with Asymmetric Boundaries

作　　者：王柳 王庄 李韵九 韦穗[1] 沈川 屈磊[1] 张成[1] Wang Liu;Wang Zhuang;Li Yunjiu;Wei Sui;Shen Chuan;Qu Lei;Zhang Cheng(Key Laboratory of Intelligent Computing&Signal Processing,Ministry of Education,Anhui University,Hefei 230601,Anhui,China)

机构地区：[1]安徽大学计算智能与信号处理教育部重点实验室,安徽合肥230601

出　　处：《激光与光电子学进展》2024年第13期170-176,共7页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(62271005);安徽省自然科学基金(2008085MF209);安徽省高等学校自然科学研究项目(2022AH050089,KJ2020ZD02)。

摘　　要：以非对称性边界条件的亚波长金光栅多层结构为模型,借助散射矩阵理论,给出反射相位与光栅边界媒质折射率之间的形式化表达。在上述表达式的基础上,以前期设计的嵌入亚波长金光栅的硅基液晶(G-LCoS)结构为例,使用时域有限差分法开展仿真实验,通过不断优化亚波长金光栅的非对称边界条件,使得G-LCoS在可见光波段下实现多波长的近2π相位调制量。所给出的形式化表达式以及优化过程可为具有动态非对称边界条件的器件,特别是微纳尺度复调制器件的设计提供参考,并且能在一定程度上解释其物理机制。In this study,the subwavelength grating multilayer structure with asymmetric boundary conditions is investigated using scattering matrix theory.A formal expression linking the reflection phase to the dielectric constant of the grating boundary medium is derived.Based on this expression,simulation experiments are conducted using the timedomain finite difference method to validate the pre designed siliconbased liquid crystal structure embedded with subwavelength gold gratings(GLCoS).Through continuous optimization of the asymmetric boundary conditions of the subwavelength gold gratings,nearly 2πphase modulation across multiple wavelengths in the visible spectrum is realized via the GLCoS.The formal expression and optimization process detailed in this paper offer reference for the design of devices with dynamic asymmetric boundary conditions,particularly complex amplitude modulation devices featuring nano/microscale structures.Additionally,this study contributes to a deeper understanding of these devices in terms of their physical mechanisms to a certain extent.

关 键 词：亚波长金光栅 非对称边界条件 散射矩阵 时域有限差分法 相位调制 

分 类 号：O436[机械工程—光学工程]