A modal solution for reflection and transmission at a chiral-chiral interface

Abstract

In this paper a modal solution for the reflection and transmission of electromagnetic waves excited by magnetic or electric line sources, above or below an interface between two chiral materials is derived. The modal solution is found by first finding a harmonic solution using the standard Fourier transform in the lateral variable. The harmonic solution is converted into a modal solution by deforming the contour of integration for the inverse transform, in the complex plane. The complete expansion for the fields is expressed as the sum of four integrals along branch cuts and two residue contributions The wave species associated with the residue contributions and each branch cut are identified For the branch cut integrals, the species are identified through asymptotic analysis of each term of the integrand. Direct, reflected lateral and surface waves of various combinations of polarizations along each segment of their path are identified. Since there are twice as many branch cut integrals and residue contributions as there are in the achiral case, many more wave species are encountered in the chiral case.