Active control of terahertz surface plasmonic wave excitation using electromagnetically induced transparency based...

Surface plasmonic waves (SPWs) that propagate at meta-dielectric interface are a good source of information carrier waves for on-chip photonic devices, where SPW excitation is one key procedure. Recently, controlling SPW excitation using metasurface methods has drawn considerable attention owing to their design flexibility, wherein achieving dynamic control is of great importance. However, most studies in the terahertz regime so far are working in a passive way or only dynamically controllable at the propagation process. In this work, an active design for controlling terahertz SPWs at the excitation process is proposed using graphene metasurfaces based on the manipulation of the electromagnetically induced transparency (EIT) effect. Large modulation depth with controllable SPW excitations is demonstrated. Our method is flexible and promising in achieving more controlling degree of freedom, which can find broadband applications in future integrated devices and systems.