Analysis of Plasmon Mode Effects in the Scattering and Absorption of THz Waves by a Dielectric Wire Wrapped in Graphene Layer with Longitudinal Slot

We study the scattering of an H-polarized plane wave by an infinite dielectric wire with a partial graphene cover. Our research is based on the hyper-singular boundary integral equation. Discretization of this equation is carried out by the Nystrom-type method that enables us to plot the dependences of extinction cross-section (ECS) on the frequency, graphene strip angular size, and its orientation angle. To explain the observed resonance effects, we derive the propagation constant of the plasmon wave guided by infinite graphene layer between two different dielectrics. We demonstrate that, for a micro-size dielectric wire and THz frequencies, the ECS resonances are in good agreement with the values obtained from the characteristic equation for the plasmon modes viewed as standing plasmon waves on the finite-width graphene strip.