Implementation of selective controlling electromagnetically induced transparency in terahertz graphene metamaterial
Implementation of selective controlling electromagnetically induced transparency in terahertz graphene metamaterial
复制标题
在太赫兹石墨烯超材料中实现选择性控制电磁感应透明度
DOI：
10.1016/j.carbon.2017.08.016
复制
发表时间：
2017-10-01
期刊：
影响因子：
10.9
通讯作者：
Jiang, Jiuxing
中科院分区：
文献类型：
--
作者：
He, Xunjun;Yang, Xingyu;Jiang, Jiuxing
设计了一种由单层石墨烯切割线谐振器阵列和紧密排列的石墨烯闭合环谐振器阵列组成的太赫兹电磁感应透明(EIT)超材料，并对其进行了数值研究。在透射谱中可以获得由两个谐振器之间的近场耦合产生的明显的透明窗口。更重要的是，由于所有单元的两个谐振器元件通过分开的石墨烯导线分别与相应的金属焊盘(焊盘1和焊盘2)相连，因此选择性掺杂石墨烯可以主动控制透明窗口的位置和幅度以及相关的群延迟和延迟带宽乘积。此外，与其他分离的石墨烯图案相比，施加栅极偏置电压可以实现更方便、更快速的调制。此外，采用两粒子模型对不同掺杂状态的石墨烯超材料的EIT行为进行了理论研究，分析结果与数值计算结果吻合较好。因此，这项工作可以为探索调制器、缓冲器和光学延迟等主动可调的慢光太赫兹器件提供一个新的平台。(C)2017爱思唯尔有限公司。保留所有权利。
A terahertz electromagnetically induced transparency (EIT) metamaterial, consisting of single-layer graphene cut wire resonator arrays with closely placed graphene closed ring resonator arrays, was designed and numerically investigated in this paper. A distinct transparency window resulting from the near field coupling between two resonators can be obtained in the transmission spectrum. More importantly, since two resonator elements of all unit cells connect respectively with the corresponding metallic pads (Pad 1 and Pad 2) by the separated graphene wires, the location and amplitude of the transparency window, and the associated group delay and delay bandwidth product can be actively controlled by the selective doping graphene. Moreover, compared with other separated graphene patterns, a more convenient and fast modulation can be realized by applying gate bias voltage. In addition, a two-particle model was employed to theoretically study EIT behaviors of the graphene metamaterial with different doping states, and the analytic results agree excellently with our numerical results. Therefore, the work could offer a new platform for exploring actively tunable slow light terahertz devices such as modulators, buffers, and optical delays. (C) 2017 Elsevier Ltd. All rights reserved.