基于二氧化钒的太赫兹可重构消色差超表面透镜  

Terahertz reconfigurable achromatic metalens based on vanadium dioxide

作　　者：王羚 高峰 滕书华 谭志国 刘文清 WANG Ling;GAO Feng;TENG Shuhua;TAN Zhiguo;LIU Wenqing(School of Electronic Information,Hunan First Normal University,Changsha410205,China;Key Laboratory of Hunan Province for 3D Scene Visualization and Intelligence Education,Hunan First Normal University,Changsha 410205,China;School of Information and Communication Engineering,Beijing University of Posts and Telecommunications,Beijing100876,China)

机构地区：[1]湖南第一师范学院电子信息学院,湖南长沙410205 [2]湖南第一师范学院三维场景可视化与智能教育湖南省重点实验室,湖南长沙410205 [3]北京邮电大学信息与通信工程学院,北京100876

出　　处：《电子元件与材料》2024年第8期1002-1008,共7页Electronic Components And Materials

基　　金：湖南省自然科学基金(2022JJ40114)。

摘　　要：消色差超表面透镜是近期研究热点。由于需同时满足聚焦相位、群时延和群时延色散,目前消色差超表面透镜的设计存在复杂度较高的缺点。基于此,通过引入相变材料二氧化钒(VO_(2),Vanadium Dioxide)为消色差超表面透镜的设计提供新的自由度,并提出了一种基于VO_(2)实现太赫兹可重构消色差超表面透镜的方法。通过切换VO_(2)的状态,可调控超表面单元引入的Pancharatnam-Berry相位,从而使得超表面透镜满足不同频率所需的相位分布,实现消色差特性。为进行验证,设计了一款工作于1.93和2.14 THz的双频可重构消色差超表面透镜,作为对比还设计了一款工作于1.93 THz的单频不可重构超表面透镜。仿真结果表明,设计的消色差超表面透镜可有效消除频率带来的焦距偏移,具有消色差特性。Widespread attention has been paid to the achromatic metalens recently.However,there are still obstacles in the design of achromatic metalens to simultaneously satisfy the required focus phase,group delay,and group delay dispersion.Therefore,vanadium dioxide(VO_(2)),a phase change material,was used to provide a new degree of freedom for designing the terahertz achromatic metalens.Here a method was presented for reconfigurable terahertz achromatic metalens based on VO_(2).Different Pancharatnam-Berry phases can be introduced by switching VO_(2)between the insulating and metallic states.Thus,the metalens can satisfy the phase profile of the metalens required for different frequencies and realize achromatic characteristics.For verification,a dual-frequency reconfigurable achromatic metalens was designed working at 1.93 THz and 2.14 THz.A single-frequency non-reconfigurable metalens was designed working at 1.93 THz for comparison.The simulation results show that the designed reconfigurable metalens can effectively reduce the focus length shift.Therefore,the metalens has achromatic characteristics.

关 键 词：太赫兹 二氧化钒 消色差 超表面透镜 

分 类 号：O441.4[理学—电磁学]