基于石墨烯超材料表面等离子体激元共振的增强太赫兹调制

基于表面等离子体共振原理,采用石墨烯超材料设计了开口环结构,用于调制太赫兹波.增加石墨烯的费米能级,改变开口环的开口距离,叠加多层石墨烯以增强石墨烯超材料的共振强度,进而增强太赫兹波调制,调制频率范围包括低频段和高频段.由于石墨烯费米能级的可调谐性,单层结构在高低两个频段的调制深度分别为81%和68%,多层结构在高低两个频段的调制深度分别增加到93%和95%,为动态调制提供了可能.该设计为调制器、吸收体等太赫兹器件的设计提供了指导和借鉴.

Enhanced Terahertz Modulation by Harvesting the Surface-plasmon-polariton Modes Based on Graphene Metamaterial

Graphene-based Split Ring Resonator (SRR) metamaterial is proposed with capacity of modulating transmitted THz waves based on the principle of surface-plasmon-polariton.The resonant strengths of plasmonic modes can be significantly enhanced by increasing the Fermi level of graphene, changing the gap distance of SRR or by stacking graphene layers, thus high modulation depth is achieved in both higher frequency region and lower frequency region.Modulation depth of 81% and 68% are achieved in the two regions, which can be further enhanced to 93% and 95%,provides a dynamical modulation based on controllable Fermi level of graphene.This graphene-based design paves the way forthe design of THz applications, such as modulators and absorbers.