基于石墨烯纳米带的中红外等离激元调控  

Mid-infrared plasmon regulation based on graphene nanoribbons

作　　者：韩晶 高扬[1] 焦威严[3] 范光华[3] 高亚臣[1] HAN Jing;GAO Yang;JIAO Wei-yan;FAN Guang-hua;GAO Ya-chen(College of Electronic Engineering,Heilongjiang University,Harbin 150080,China;College of Science,Heilongjiang Institute of Technology,Harbin 150050,China;College of Physics,Harbin Institute of Technology,Harbin 150001,China)

机构地区：[1]黑龙江大学电子工程学院,黑龙江哈尔滨150080 [2]黑龙江工程学院理学院,黑龙江哈尔滨150050 [3]哈尔滨工业大学物理学院,黑龙江哈尔滨150001

出　　处：《中国光学》2020年第3期627-636,共10页Chinese Optics

基　　金：黑龙江省自然科学基金(No.F2018027,No.LH2019F047)。

摘　　要：石墨烯在中红外和太赫兹波段可以产生表面等离激元,并且通过合理设计还可以对其表面等离激元进行调控。基于此,本文设计了一种共振可调结构。通过在电介质基底上沉积不同宽度的单层石墨烯条带,引入纳米尺度上的不连续性,从而有效控制石墨烯与光的相互作用。使用时域有限差分法对该结构的光谱和电磁场分布进行了理论研究。结果表明:当所设计的结构与入射光耦合时,会出现多个共振增强的吸收峰;改变每个周期内石墨烯条带的数目、带宽和带间距,可以控制共振峰的个数、位置和强度;另外,施加不同的偏置电压可以改变石墨烯带的费米能级,从而实现共振峰位置和强度的动态调控;该结构可以在较宽光谱范围内调控石墨烯等离激元。本文研究为设计中红外波段基于石墨烯的传感、滤波、吸收等器件提供了理论基础。Surface plasmon can be produced in graphene in the mid-infrared and terahertz waveband regimes,and the regulation for surface plasmon can be achieved by a reasonable design.On the basis of above,a resonant tunable structure was designed.By depositing single layers of graphene ribbons with different widths on a dielectric substrate,discontinuities in nanoscale were introduced,thereby effectively controlling the interaction of graphene with light.The spectral and electromagnetic field distributions of the structure were the-oretically studied using the finite difference time domain method.The results showed that when the designed structure was coupled with the incident light,there would be multiple resonance enhanced absorption peaks.By changing the number,width and distance of the graphene ribbons in each period,the number,position,intensity of the resonance peak can be controlled.In addition,the Fermi energy level of graphene can be changed by applying different bias voltages,so the position and intensity of resonance peak can be adjusted dynamically.Therefore,with this structure graphene plasmon resonance can be regulated over a wide spectral range.This study provides a theoretical basis for the design of the graphene-based sensors,filters and absorbers in infrared regime.

关 键 词：石墨烯条带 表面等离激元 时域有限差分 法布里-珀罗模型 费米能级 

分 类 号：TN29[电子电信—物理电子学]