Lifetime of Enhanced Graphene Surface Plasmon and Superstrate Sensitivity

We investigated the field enhancement and lifetime of tuning surface plasmon in zero-thickness nanostructured graphene patches. The graphene surface plasmon (GSP) resonance mechanism mainly originates from the contribution, that the periodical structure can provide strong coupling of GSP modes into the incident light field, which can enhance GSP resonance and the local field. And consequently, it facilitates the tuning of the patch modes by changing Fermi energy, carrier mobility, and superstrate refractive index, respectively. We can control precisely the resonant wavelengths, field enhancement, and lifetime of the patch GSP modes by using finite-difference time-domain (FDTD) simulation and coupled mode theory (CMT). The sensitivity is described by varying the refractive index of the superstrate. The theoretical descriptions and data fitting of lifetime of GSP modes are useful for graphene application.