Topics in Guided-Wave Propagation Through Gyromagnetic Media: Part I - The Completely Filled Cylindrical Guide

The characteristic equation for the propagation constants of waves in a filled circular guide of arbitrary radius is written in terms of magnetizing field and a carrier density, which are shown essentially to determine the dielectric and permeability tensors for a gas discharge plasma and for a fertile. The complex structure of the spectrum of propagation constants and its dependence upon radius and the two parameters are analyzed by a semigraphical method, supplemented by exact formulae in special regions. Thus the course of individual modes may be charted with fair accuracy. 1. I N T R O D U C T I O N Any material medium which propagates electromagnetic disturbances possesses a local electric or magnetic structure and it is just the motion of the electric or magnetic carriers under the fields of the disturbance that determines how the propagation takes place. If a dc magnetic field be applied to the medium one may expect the local response to be altered and, consequently, to find changes in the character of the propagation. Gyromagnetic media are those for which such changes are sufficiently large to be experimentally significant. For plane waves and for optical frequencies the experimental effects and their explanation have been familiar for a great many years. The non-reciprocal rotation of the plane of polarization of light travelling parallel or antiparallel to an applied dc magnetic field, which is known as the Faraday effect, is such a phenomenon. So also is the fact that the medium becomes doubly refracting for arbitrary directions of propagation.