Wang Luyao, Gao Zijie, Hou Zhenlin, Song Jinmei, Liu Xiaoyu, Zhang Yifei, Wang Xiaodong, Yang Fuhua, Shi Yanpeng
School of Microelectronics, Shandong University, Jinan 250100, China.
Engineering Research Center for Semiconductor Integrated Technology, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.
ACS Omega. 2021 Feb 4;6(6):4480-4484. doi: 10.1021/acsomega.0c06082. eCollection 2021 Feb 16.
In this work, an analogue of electromagnetically induced transparency (EIT) is excited by a periodic unit consisting of a silicon rectangular bar resonator and a silicon ring resonator in terahertz (THz). The analogue of the EIT effect can be well excited by coupling of the "bright mode" and the "dark mode" supported by the bar and the ring, respectively. Using the semimetallic properties of graphene, active control of the EIT-like effect can be realized by integrating a monolayer graphene into THz metamaterials. By adjusting the Fermi energy of graphene, the resonating electron distribution changes in the dielectric structures, resulting in the varying of the EIT-like effect. The transmission can be modulated from 0.9 to 0.3 with the Fermi energy of graphene placed under the ring resonator mold varying from 0 to 0.6 eV, while a modulation range of 0.9-0.3 corresponds to Fermi energy from 0 to 0.3 eV when graphene is placed under the rectangular bar resonator. Our results may provide potential applications in slow light devices and an ultrafast optical signal.
在这项工作中，太赫兹（THz）频段由硅矩形棒谐振器和硅环形谐振器组成的周期性单元激发了电磁诱导透明（EIT）的一种类似物。EIT效应的类似物可以分别通过由棒和环所支持的“亮模式”和“暗模式”的耦合很好地激发。利用石墨烯的半金属特性，通过将单层石墨烯集成到太赫兹超材料中，可以实现对类EIT效应的主动控制。通过调整石墨烯的费米能，介电结构中的共振电子分布发生变化，从而导致类EIT效应的改变。当置于环形谐振器模下方且石墨烯的费米能从0变化到0.6电子伏特时，透射率可从0.9调制到0.3；而当石墨烯置于矩形棒谐振器下方时，0.9 - 0.3的调制范围对应费米能从0到0.3电子伏特。我们的结果可能在慢光器件和超快光信号方面提供潜在应用。
