Terahertz on-chip 2-to-4 decoder based on the manipulation of surface plasmon polaritons

In recent years, the excitation of surface plasmon polaritons (SPPs) on metasurfaces has attracted considerable research interest, as the design flexibility of metasurfaces has enabled more extensive and in-depth investigations into dynamic SPPs modulation. To advance the theoretical understanding and practical applications in this field, this study designs a graphene-based metasurface capable of actively controlling SPPs excitation behavior. By leveraging the electrically tunable conductivity of graphene to manipulate the resonance loss of dark modes, we achieve active control of SPPs excitation along the ± x directions, realizing a 2-to-4 decoder functionality. This innovative approach integrates active SPPs excitation control with the operational principles of logic circuit devices, thereby proposing strategies for optical logic computing and optical switching applications, which demonstrate significant potential for practical implementations.