Tunable dual plasmon-induced transparency and slow-light analysis based on monolayer patterned graphene metamaterial

Abstract

We propose a novel terahertz metamaterial structure based on patterned monolayer graphene. This structure produces an evident dual plasmon-induced transparency (PIT) phenomenon due to destructive interference between bright and dark modes. Since the Fermi level of graphene can be adjusted by an external bias voltage, the PIT phenomenon can be tuned by adjusting the voltage. Then the coupled-mode theory (CMT) is introduced to explore the internal mechanism of the PIT. After that, we investigate the variation of absorption rate at different graphene carrier mobilities, and it shows that the absorption rate of this structure can reach 50%, which is a guideline for the realization of graphene terahertz absorption devices. In addition, through the study of the slow-light performance for this structure, it is found that its group index is as high as 928, which provides a specific theoretical basis for the study of graphene slow-light devices.

Dynamically tunable multiple plasmon-induced transparency effect based on monolayer graphene structure system with rectangular defect cavities

“…In addition, since the development of metamaterials [4][5][6][7], plasmon-induced transparency (PIT) has become the major research area [8][9][10]. The PIT accounts for the transparent result stemming from destructive interference between bright and dark modes, standing for direct and indirect excitation pathways, respectively [11,12]. Usually, the bright mode also presents the full width at half maximum (FWHM) on the absorption spectrum, which researchers can potently combine with incident light.…”