Dispersion of Surface Plasmon-Polaritons of Graphene Loaded on Side-Walled Grating: A Simulation and Theoretical Study

The dispersion characteristics of graphene's surface plasmon-polaritons (SPPs), loaded on the dielectric grating with metal side-walls, were mathematically modeled, theoretically analyzed and numerically simulated. The influence of the grating width, chemical potential and layer-number of graphene on the behavior of SPPs was investigated. The simulated results show that the grating width, chemical potential and layer-number of graphene all have a major impact. To be specific, as the width increases, the e-field amplitude increases, the frequency point and initial frequency of dispersion curve decrease, the cutoff frequency decreases to 0 THz at 90 μm, indicating that no SPPs show up in low frequency band. Besides, as the chemical potential and layer-number increase, the dispersion curve shifts upwards, accompanied by a decreasing frequency point. The SPPs were found to be capable of emitting THz electromagnetic wave.