摘要
提出了一种在超表面中嵌入二氧化钒(VO2)从而对太赫兹波进行动态调控的方法。VO2在68℃左右会发生绝缘体到金属的相变,导致其电导率发生4~5个数量级的显著变化。超表面由一个双开口金属谐振环阵列以及金属环开口处嵌入的VO2结构组成。仿真结果表明,通过改变VO2的电导率,太赫兹波可以实现高频与低频之间的谐振模式的切换。值得注意的是,这种模式转换不仅可以在实验中通过直接改变环境温度实现,还可以通过激光和强场太赫兹的泵浦完成。这种多样化的激励为该超表面在实际多场景应用中动态调控太赫兹波提供了参考。
Objective Terahertz(THz)is a electromagnetic wave with the frequency range of 0.1‒10 THz,and is gradually playing an important role in many fields.However,because traditional electronic and optical design methods consider the adjacent microwave and infrared optical bands,the application of the THz band is not easy to directly expand,which will undoubtedly greatly hinder further development of THz technology.Thus,there is an urgent need for new THz device design methods to solve this difficulty.Metamaterials are composed of a series of micro-and nanostructures with artificially designed periodic arrangements,whose size,shape,and distribution can produce optical responses that natural materials do not exhibit after careful design.Two-dimensional metamaterials,i.e.,metasurfaces,with a simple process flow and low processing cost,have gradually replaced metamaterials in recent years and have become a popular research topic.The application of metasurfaces to THz technology overcomes the limitations of traditional materials,contributing to their development.With the increasing demand for corresponding applications,researchers have shifted their attention from single passive hypersurfaces to tunable active metasurfaces.These tunable metasurfaces are often dependent on several tunable materials.In particular,in the THz band,vanadium dioxide(VO2)is an excellent tunable material that is being actively investigated by researchers due to its abrupt change in conductivity of four to five orders of magnitude before and after the phase transition temperature,which allows it to complete the insulating to the metallic phase transition.Methods A metasurface comprising a periodic array of double-gap split-ring resonators,with VO2 structures embedded in the gaps,was considered in this study.The spectral responses to different VO2 conductivities and electric field distribution images of the corresponding modes were first simulated using the commercial simulation software,CST.Next,samples were obtained via conventional lithography an
作者
王磊
李花
王永杰
张彩虹
吴敬波
范克彬
金飚兵
陈健
吴培亨
Wang Lei;Li Hua;Wang Yongjie;Zhang Caihong;Wu Jingbo;Fan Kebin;Jin Biaobing;Chen Jian;Wu Peiheng(Research institute of Superconductor Electronics(RISE),School of Electronic Science and Engineering,Nanjing University,Nanjing 210023,Jiangsu,China;Purple Mountain Laboratories,Nanjing 211111,Jiangsu,China)
出处
《中国激光》
EI
CAS
CSCD
北大核心
2023年第17期184-190,共7页
Chinese Journal of Lasers
基金
国家重点研发计划(2017YFA0700202,2021YFB2800701)
国家自然科学基金(62222106,61871212,92163216,62071217,62027807,62288101)
中央高校基本科研业务费专项资金。
关键词
光电子学
太赫兹
超材料与超表面
二氧化钒
激光泵浦
强场太赫兹
optoelectronics
terahertz
metamaterial and metasurface
vanadium dioxide
laser pump
strong-field terahertz
