Metal-graphene hybrid terahertz metamaterial based on dynamically switchable electromagnetically induced transparency effect and its sensing performance

Abstract

A dynamically switchable electromagnetically induced transparency (EIT) based on metal-graphene hybrid metamaterial is proposed. The EIT metamaterial consists of two split-ring resonator (SRRs) and two orthogonal cut-wires (CWs) with different length. The EIT metamaterial illuminated by y-polarized and x-polarized incident waves exhibits two different EIT effects, which can be explained by multipole scattering theory and three-dimensional schematic diagrams. The simulated EIT spectra are almost identical to the theoretical EIT spectra calculated by the two-particle model. Two EIT effects and theirs group delays can be dynamically tunable by manipulating the Fermi level of graphene on two SRRs. Moreover, EIT metamaterial shows good sensing performance with the sensitivities of 0.185 THz/RIU and 0.160 THz/RIU in the x and y polarization directions, respectively. Our EIT metamaterial realizes dynamically switchable EIT effect and provides a novel approach for applications in slow light devices and sensors.