Plasmon-induced transparency effect in hybrid terahertz metamaterials with active control and multi-dark modes  

作　　者：Yuting Zhang Songyi Liu Wei Huang Erxiang Dong Hongyang Li Xintong Shi Meng Liu Wentao Zhang Shan Yin Zhongyue Luo 张玉婷;刘嵩义;黄巍;董尔翔;李洪阳;石欣桐;刘蒙;张文涛;银珊;罗中岳(Guangxi Key Laboratory of Optoelectronic Information Processing,School of Optoelectronic Engineering,Guilin University of Electronic Technology,Guilin 541004,China)

机构地区：[1]Guangxi Key Laboratory of Optoelectronic Information Processing,School of Optoelectronic Engineering,Guilin University of Electronic Technology,Guilin 541004,China

出　　处：《Chinese Physics B》2022年第6期750-758,共9页中国物理B（英文版）

基　　金：supported by the National Science and Technology Major Project(Grant No.2017ZX02101007-003);the National Natural Science Foundation of China(Grant No.61965005);the National Natural Science Foundation of China(Grant No.62105187);the Natural Science Foundation of Guangxi Province(Grant No.2019GXNSFDA185010);Guangxi Distinguished Expert Project,Foundation of Guangxi Key Laboratory of Optoelectronic Information Processing(Grant No.GD20104);the Natural Science Foundation of Shandong Province,China(Grant No.ZR2021QF010);the Innovation Project of Guang Xi Graduate Education(Grant No.YCSW2020158)。

摘　　要：We numerically demonstrate a photo-excited plasmon-induced transparency(PIT)effect in hybrid terahertz(THz)metamaterials.The proposed metamaterials are regular arrays of hybrid unit cells composed of a metallic cut wire and four metallic split-ring resonators(SRRs)whose gaps are filled with photosensitive semiconductor gallium arsenide(GaAs)patches.We simulate the PIT effect controlled by external infrared light intensity to change the conductivity of GaAs.In the absence of photo excitation,the conductivity of Ga As is 0,thus the SRR gaps are disconnected,and the PIT effect is not observed since the dark resonator(supported by the hybrid SRRs)cannot be stimulated.When the conductivity of GaAs is increased via photo excitation,the conductivity of Ga As can increase rapidly from 0 S/m to 1×10^(6)S/m and GaAs can connect the metal aluminum SRR gaps,and the dark resonator is excited through coupling with the bright resonator(supported by the cut wire),which leads to the PIT effect.Therefore,the PIT effect can be dynamically tuned between the on and off states by controlling the intensity of the external infrared light.We also discuss couplings between one bright mode(CW)and several dark modes(SRRs)with different sizes.The interference analytically described by the coupled Lorentz oscillator model elucidates the coupling mechanism between one bright mode and two dark modes.The phenomenon can be considered the result of linear superposition of the coupling between the bright mode and each dark mode.The proposed metamaterials are promising for application in the fields of THz communications,optical storage,optical display,and imaging.

关 键 词：METAMATERIAL plasmon induced transparency photo-excited TERAHERTZ 

分 类 号：O441.4[理学—电磁学] O53[理学—物理]