Scattered field from a single/double negative grounded slab with rough interface

Abstract

In this paper, we assume a dispersive grounded slab with rough interface to study the scattering properties using the perturbation theory (PT). The Lorentz-Drude model is used to find out the positive/negative permittivity and permeability of the slab. For different operating frequencies, the dispersive slab behaves as epsilon negative (ENG), double negative (DNG), mu negative (MNG) and double positive (DPS) material. Using the PT, the unknown scattering and transmission coefficients are evaluated. It is observed that the period of the surface affects the scattering from DNG slab more than that from DPS slab. For small period, the scattered field from the ENG slab is very small while it is large for MNG slab. Moreover, as the thickness of the slab is changed, the scattering behavior of ENG slab shows an increasing trend opposite to that of the MNG slab. The roughness of the Gaussian surface has dominant effect on the scattering compared with the material properties of the slab.