Generalized WKB Approximation for Stratified Isotropic Chiral Media with Obliquely Incident Plane Wave

Abstract

The WKB method and its generalization are extended to stratified chiral media for waves with oblique incidence. Wave propagation in chiral media inhomogeneous in one space coordinate is considered through normalized wave fields, a certain combination of the electric and magnetic fields, which are slightly coupled in slightly inhomogeneous media. Omitting the coupling leads to the WKB solution for waves propagating without reflection. The reflection effect is obtained as a first order correction to the WKB solution. For sufficiently slowly varying media, the reflection dyadic due to the stratification can be expressed in closed integral form.