Analysis of diffracted waves from a grounded uniaxial chiral medium with a plane metallic grating

Abstract

A 4×4 matri×-based analysis of the electromagnetic waves diffracted by a grounded slab of uniaxial chiralmedium with a plane metallic grating has been presented. In the analysis, the total fields are given by the superposition of the current-independent primary fields and the scattered fields depending on the currentsinduced on the grating. The scattered fields are expanded in terms of Floquet modes. The coupled mode equations which are derived for the uniaxial chiral media give the general solutions of fields as the superposition of left and right-handed elliptically-polarized eigen modes. The unknown currents on the grating are determined by applying Galerkin's method to the condition of the perfect conductivity on the grating. Both the direction of the optical axis of the uniaxial anisotropy and that of the incident wave vector are assumed to be perpendicular to the strip conductors of the grating. In the numerical computation, the polarization characteristics of diffracted waves are investigated.