基于半导体硅电导率的可调性,设计了一种基于金属短线(CW)和圆形开口谐振环(SRR)的可控电磁诱导透明(EIT)结构,实现了对电磁诱导透明(EIT)效应的主动调控。研究发现,当半导体硅的电导率为1 S/m时,透射谱在1.33 THz附近呈现出透射率约为94%的窄透明窗口。当电导率为5000 S/m时,透射率变为58%;当电导率为15000 S/m时,EIT效应基本消失,调控效率达到了66%。利用耦合模理论对不同电导率的透射谱进行拟合,发现拟合曲线与透射谱非常吻合,这表明仿真结果和理论计算结果是一致的。仿真和计算结果表明,当硅的电导率增大时,暗模式的阻尼率增大,其损耗也增大,当电导率增大到一定值时,暗模式的谐振不能被激发,EIT效应消失。

Based on the tunable conductivity of semiconductor silicon, a controllable electromagnetic induced transparency (EIT) structure composed of cut wires (CW) and split-ring resonators (SRR) is designed, and the active modulation of EIT effect is realized. It is found that a narrow transparency window with a transmittance of about 94% appears in the transmission spectrum at near 1.33 THz when the conductivity of semiconductor silicon was 1 S/m. When the conductivity increases to 5000 S/m, the transmittance becomes 58% and when the conductivity approaches 15000 S/m, the EIT effect almost disappears, and the modulation efficiency approaches 66%. The transmission spectra under different conductivities are consistent with their fitting curves by the coupled mode theory, indicating that the simulation results are in accord with the theoretical calculation findings. Both the simulation and calculation results show that the damping ratio of dark mode and the loss increase when the electrical conductivity of silicon increases. When the electrical conductivity reaches a certain value, the resonance of dark mode is not be stimulated and thus the EIT effect disappears.