摘要
基于超材料的太赫兹吸收器在开关、调制和检测方面展现出了极大的应用前景,目前已提出了多种方案来有效操纵太赫兹波。但是大多数设计的结构单元吸收性能较差且难以实现吸收响应的动态可调。本文提出了一种基于耦合图案化石墨烯结构的宽带可调太赫兹超材料吸收器,该器件由石墨烯-介质-金属的三明治结构组成。仿真结果表明:所提出设计的吸收效率在90%以上的带宽达到了2.9 THz,并分别在6.78 THz和8.44 THz处达到了完美吸收,相应的吸收率为99.12%和94.31%。通过改变石墨烯的费米能级,能够对宽带吸收光谱的幅值在相同的频率范围内实现主动可调。引入阻抗匹配原理和表面电流分布分别研究了形成宽带吸收光谱的物理机制。该吸收器还具备在宽入射角范围内仍保持良好吸收的性能。因此,本文所提出的吸收器结构设计为后续智能化、集成化和小型化的太赫兹超材料功能器件的研究提供了新的途径。
The terahertz absorber based on metamaterial has shown great application prospects in switching,modulation and detection. Many schemes have been proposed to effectively manipulate terahertz waves. However,most of the designed structural elements have poor absorption performance and are difficult to achieve dynamic adjustment of absorption response. A wideband tunable terahertz metamaterial absorber based on a coupled patterned graphene structure is proposed in this paper. The device consists of a graphene-dielectric-metal sandwich structure.The simulation results show that the proposed design achieves 2.9Thz bandwidth with absorption efficiency above90%, and achieves perfect absorption at 6.78Thz and 8.44Thz, respectively, with corresponding absorption rates of99.12% and 94.31%. By changing the Fermi energy level of graphene, the amplitude of the broadband absorption spectrum can be actively adjustable in the same frequency range. The physical mechanism of forming wideband absorption spectrum is studied by introducing impedance matching principle and surface current distribution. The absorber also has the performance of maintaining good absorption in a wide incidence Angle range. Therefore, the structure design of the absorber proposed in this paper provides a new approach for the subsequent study of intelligent, integrated and miniaturized terahertz metamaterial functional devices.
作者
向飞宇
朱文婷
马福渊
骆岩红
Xiang Feiyu;Zhu Wenting;Ma Fuyuan;Luo Yanhong(Northwest Minzu University,College of Electrical Engineering,Lanzhou 730106,China)
出处
《科学技术创新》
2022年第12期29-32,共4页
Scientific and Technological Innovation
基金
2022年西北民族大学大学生创新创业训练计划项目资助(项目编号:X202210742233)。
关键词
太赫兹波
石墨烯
动态可调
超材料
宽带吸收
THZ wave
Graphene
Dynamic adjustable
Metamaterials
Broadband absorption
