Longitudinal- and transverse-operators formalism for chiral media: Application to guided structures filled with chiral materials

In this paper an approach based on the calculation of longitudinal and transverse operators is presented. The paper is devoted to the interesting topic of electromagnetic-wave propagation in complex (chiral) media. The studied process allows the analysis of guidedstructures with chiral-medium components. In this case the equations are continuously coupled. Using the longitudinal equations, we analyze wave propagation in a parallel-plate chirowaveguide consisting of two parallel perfectly conducting planes filled with a lossless, homogeneous, isotropic chiral material. The main feature of the guides is that the propagation modes are always hybrid. In addition, bifurcated modes exist with the same cutoff-frequency values and unequal propagation characteristics. We address here the issue of wave propagation in a rectangular chirowaveguide, by means of longitudinal and transverse operators. This topic was first addressed by Engheta and Pelet. (IEEE Trans. Antenna Propag. 38, 90 (1990)). We rederive their results, using a method based on a new mathematical approach that seems to be original.PACS Nos.: 41.20.Jb