Source-excited electromagnetic fields on cylindrically stratified guiding structures in a gyrotropic medium

Summary form only given. Electromagnetic fields excited by sources in cylindrically stratified regions possessing azimuthal symmetry can be represented as a superposition of waves propagating either along the direction of the axis of symmetry (here taken as z-direction) or along the direction transverse thereto. The corresponding representations of source-excited fields have the form of either an eigenfunction expansion or Fourier-type integrals of continuous wave terms. This article discusses the methods for representing the source-excited electromagnetic field on an open cylindrical guide immersed in a gyrotropic medium (such as a magnetoplasma, for example) and aligned with an ambient static magnetic field, in the light of an upsurge of interest in this area. We particularly consider two guiding structures surrounded by a uniform gyrotropic background medium: (i) a radially nonuniform gyrotropic cylinder and (ii) a perfectly conducting cylinder with (an)isotropic/gyrotropic coating. We investigate which types of eigenmodes can be expected in such structures. Application of the above representations are discussed in a detailed manner for a variety of particular cases of interest (e. g., density filaments in laboratory and space plasmas, cylindrical metallic antennas in gyrotropic media, etc.) and a survey of experimental evidence of the obtained solutions are presented.