Active control of polarization-dependent terahertz surface plasmonic wave excitation using coupled graphene-metal hybrid metasurfaces

Abstract

Active control of terahertz surface plasmonic wave (SPW) intensity in the propagation direction holds substantial significance for advanced terahertz functional devices. In this study, we propose a graphene-metal hybrid split-ring slit resonator (SRSR) array metasurfaces and employ the concept of electromagnetically induced transparency (EIT) to achieve excitation of asymmetric SPWs under various polarization states. By individually integrating two graphene ribbons into the two split-ring slit gaps and applying different bias voltages, we observed a gradual transition in the excitation behavior of asymmetric terahertz SPWs, ultimately resembling that of a single SRSR. Near-field simulations reveal that this phenomenon is attributed to the short-connection effect of graphene. Our proposed graphene-metal active hybrid metasurface introduces a novel approach to realize active SPWs devices, holding potential applications in terahertz on-chip communication.