Surface plasmon resonance characteristics of a graphene nano-disk based on three-dimensional boundary element method

Compared with the commonly used simulation algorithms such as Finite Element Method (FEM) and Finite-Difference Time-Domain (FDTD) method, the Boundary Element Method (BEM) has the advantages of high accuracy, small memory consumption, and ability to deal with complex structures. In this paper, the basic principle of three-dimensional BEM is given, the corresponding program based on C++ language is written, and the Surface Plasmon Resonance (SPR) characteristics of a graphene nano-disk structure are studied. The Scattering Cross-Section (SCS) spectral lines of a graphene nano-disk under different chemical potentials, as well as the distributions of electromagnetic fields at the resonance wavelengths are calculated. The electromagnetic response of the graphene nano-disk in the infrared band is analyzed. In addition, considering the common corrugations of graphene materials caused by defects during processing, we study the influence of the geometric parameters of a convex structure in the center of the graphene nano-disk on the resonance intensity, wavelength and field distributions. A spring oscillator model of charge movement is used to explain the simulation results.