带边墙的三维光栅石墨烯表面激元辐射的色散特性研究  

Dispersion of Surface Plasmon-Polaritons of Graphene Loaded on Side-Walled Grating: A Simulation and Theoretical Study

作　　者：叶青青 刘文鑫[1] Ye Qingqing;Liu Wenxin(Key Laboratory of High Power Microwave Sources and Technologies,Institute of Electronics,Chinese Academy of Sciences,Beifing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院电子学研究所高功率微波源与技术重点实验室,北京100190 [2]中国科学院大学,北京100049

出　　处：《真空科学与技术学报》2018年第11期985-989,共5页Chinese Journal of Vacuum Science and Technology

基　　金：基于X射线LIGA技术的太赫兹行波管研究(u1832193);微纳强流真空电子光学系统的集成方法与关键技术(61831001)

摘　　要：主要推导了平行运动电子注激励下,三维介质光栅的石墨烯表面等离子体激元的色散方程和电场的幅值公式,数值计算结果表明,电子注与色散曲线交点对应的频率与电场幅值最大值的频率一致,证明了理论推导公式的正确性。分析了介质光栅宽度对色散方程与电场幅值的影响,发现宽度变小时,电场幅值变小,工作点的频率变高,并且色散曲线的初始频率变大,即出现了截止频率,因此三维介质光栅的石墨烯表面等离子体激元无法工作在较低频段。本文还提出石墨烯的化学势变高,层数增加时,色散曲线上移,对应工作频点升高。通过求解电场方程,可以清楚看到石墨烯的表面等离子体激元以及转化的太赫兹辐射。The dispersion characteristics of graphene＇ s surface plasmon-polaritons （ SPPs）, loaded on the dielectric grating with metal side-walls, were mathematically modeled, theoretically analyzed and numerically simulated. The influence of the grating width, chemical potential and layer-number of graphene on the behavior of SPPs was investigated. The simulated results show that the grating width, chemical potential and layer-number of graphene all have a major impact. To be specific, as the width increases, the e-field amplitude increases, the frequency point and initial frequency of dispersion curve decrease, the cutoff frequency decreases to 0 THz at 90 μm,indicating that no SPPs show up in low frequency band. Besides, as the chemical potential and layer-number increase, the dispersion curve shifts upwards, accompanied by a decreasing frequency point. The SPPs were found to be capable of emitting THz electromagnetic wave.

关 键 词：介质光栅 石墨烯 表面等离子体激元 电子注 

分 类 号：TN124[电子电信—物理电子学]