Spectral-domain dyadic Green's functions for surface current excitation in planar stratified bianisotropic media

Abstract

A rigorous formulation of the spectral-domain dyadic Green's functions for surface current excitation in planar stratified bianisotropic media is presented. The media may consist of any number of layers bounded by optional perfect electric/magnetic conducting walls. The surface current can be impressed along any of the layer interfaces. Both electric and magnetic dyadic Green's functions are derived simultaneously based on the principle of scattering superposition. For the primary dyadic Green's functions associated with a two-layered semiinfinite medium, their source consequents are determined directly from the elementary boundary conditions across the interface. An alternative approach to obtain these source consequents is also devised by considering their relationship with those of unbounded dyadic Green's functions. For the scattered dyadic Green's functions, their scattering coefficient matrices are determined without cumbersome operations using the concepts of effective reflection and transmission of outward-bounded and inward-bounded waves. This approach provides good physical insights to the scattering mechanism and leads to compact and convenient representations. To illustrate the application of general dyadic Green's function expressions, the configuration of a grounded bianisotropic slab embedded in isotropic half-space is considered explicitly.