Electromagnetic surface waves supported by a resistive metasurface-covered metamaterial structure

Sci Rep. 2020 Sep 23;10(1):15548. doi: 10.1038/s41598-020-72396-7.

Abstract

This study examines the analytical and numerical solution of electromagnetic surface waves supported by a resistive metasurface-covered grounded metamaterial structure. To simulate the metamaterial, the Kramers-Kronig relation based on the causality principle is used, while the modeling of the resistive metasurface has been done by implementing the impedance boundary conditions. The analytical expressions for the field phasors of surface waves are developed for the transverse magnetic (TM) polarized mode and transverse electric (TE) polarized mode. The characteristic equations are computed for both modes, and the unknown propagation constant is evaluated numerically in the kernel. After computation, the dispersion curves, electric field profiles, effective mode index ([Formula: see text]), and phase speeds ([Formula: see text]) are presented for both the TM and TE polarized modes. To study the tunability of surface waves, the influence of the thickness of the metamaterial slab ([Formula: see text]), effective permittivity of the metamaterial ([Formula: see text]), thickness of the resistive metasurface ([Formula: see text]), and effective permittivity of the metasurface ([Formula: see text]) on all the numerical results has been studied. However, the geometrical parameters are found to be more sensitive to the effective mode index ([Formula: see text]) and phase speed ([Formula: see text]) of the surface waves. The results are consistent with the published results, which reflects the accuracy of the work. It is concluded that the appropriate choice of parameters can be used to achieve surface waves with the desired characteristics in the GHz range. The present work may have potential applications in surface waveguide design, surface wave speed controllers, surface communication devices, and light trapping configurations.