基于频率选择表面的太赫兹FP干涉滤光片设计  

Design of Terahertz FP Interference Filter Based on Frequency Selective Surfaces

作　　者：廖文焘 金尚忠 李宏光[2] 郭宇烽 解琪[2] Liao Wentao;Jin Shangzhong;Li Hongguang;Guo Yufeng;Xie Qi(College of Optical and Electronic Technology,China Jiliang University,Hangzhou 310018,Zhejiang,China;Xi'an Institute of Applied Optics,Xi'an 710065,Shaanxi,China)

机构地区：[1]中国计量大学光学与电子科技学院,浙江杭州310018 [2]西安应用光学研究所,陕西西安710065

出　　处：《中国激光》2024年第2期204-211,共8页Chinese Journal of Lasers

基　　金：装备发展部预先研制项目(31517050104)。

摘　　要：在太赫兹频段,为解决FP干涉滤光片反射率低、适用频率范围小及角度稳定性差的问题,设计了一种新的太赫兹频率选择表面结构。首先进行了仿真分析,确定了结构的硅片厚度和金属网栅层数,并对参数进行了优化。然后对该结构的传输特性和角度稳定性进行了仿真,该结构在入射倾斜角0°~45°范围内具有较好的稳定性,最后加工出滤光片实物,对仿真结果的准确性进行验证。在太赫兹波垂直入射的情况下,实物测量结果与仿真结果基本吻合,在1.34~2.34 THz频率范围内,反射率和透射率分别为91.0%~98.4%和0.7%~8.0%,满足FP干涉滤光片高反射率、低透射率要求。Objective The Fabry-Perot(FP)interferometer is an effective tool for measuring the wavelengths of terahertz waves.It exhibits the advantages of easy adjustment,simple structure,quick measurement,and high accuracy,making it a highly effective tool in the field of wavelength measurements.The FP interferential filter should satisfy the requirements of high reflectivity and low transmissivity.Interference fringes generated by low-reflectivity filters exhibit low precision and resolution,leading to increased errors in wavelength measurements.Natural nonmetallic materials exhibit low reflectivity for Terahertz waves.However,by depositing a periodic metal array on their surface,a frequency-selective surface(FSS)can significantly enhance their reflectivity for Terahertz waves.Currently,this is the preferred method for designing FP interferential filters.Extant studies indicate that the dimensions of FSS structural units decisively impact Terahertz transmission characteristics.Many researchers examined metal array structures,but the compatibility among performance parameters,such as reflectivity,applicable frequency range,and angle stability,has not been satisfactorily realized.To further explore the relationship between the FSS structure and FP interferential filter performance and address the issues presented in extant research,in this study,a new FSS structure is proposed.Methods The FSS structure proposed in this study utilize high-resistance silicon and copper.Firstly,in the frequency range of 1.0‒3.0 THz,the relationship between thickness of high-resistance silicon and resonance period is simulated using the HFSS software.A high-resistance silicon with a thickness of 100μm is determined as the substrate material.In the frequency range of 1.2‒2.5 THz,the relationship between number of metal grid layers and Terahertz wave transmission characteristic is simulated,confirming the use of a single-layer grid for the FSS structure.The influence of various structural parameters on Terahertz wave transmission characteris

关 键 词：材料 太赫兹超材料 频率选择表面 FP干涉 金属网栅 高反射率 

分 类 号：O43[机械工程—光学工程]