Original Article

TE-wave propagation in a hollow circular waveguide filled with a graded multilayered dielectric medium

KTH Royal Institute of Technology, Teknikringen 29, Stockholm 114 28, Sweden

^* e-mail: balwan@kth.se

Received: 4 November 2024
Accepted: 5 May 2025
Published online: 14 July 2025

Abstract

In this paper, we study transverse electric (TE) wave propagation inside a hollow circular waveguide filled with a lossy graded multilayered dielectric composite. The dielectric composite grading and the wave propagation are directed along the z-direction. The z-dependent permittivity of the dielectric composite is modeled using a periodic sinusoidal function. The exact analytical solutions to Maxwell's equations are obtained, and the field solutions and wave behavior confirm the expected properties of a lossy graded multilayered dielectric medium inside a hollow circular waveguide. Thereafter, through a numerical study performed using the commercial software COMSOL Multiphysics, we show that the analytical and numerical results are in perfect agreement. The analytical model applies to any combination of the material parameters relevant to the graded multilayered dielectric medium. The significance of the proposed method is that it can be utilized for analytically studying wave propagation and wave phenomena in a variety of media with characteristics including, but not limited to, periodicity, grading, negative refraction, and spatial- and frequency dependence. The validity is not restricted to any given frequency regime, therefore, allowing the proposed method to be useful for different types of applications, such as super-resolution imaging, electromagnetic cloaking, sub-wavelength focusing, and microwave absorbers.