Theory of high-frequency guided waves in a plasma-loaded waveguide

Abstract

The theory of high-frequency guided waves in a plasma-loaded waveguide is presented. The formulation is based on kinetic theory. The theory includes the effects of finite electron/ion temperatures and radial gradients in the plasma density and particle temperatures. The inclusion of gradients into the formalism results in three, coupled, second-order, ordinary differential equations in the plasma fields. These equations show a singularity on the plasma axis (r=0); regularization of the field equations at the singular point leads to constraints on the plasma fields that yield the necessary boundary conditions at r=0. Using the vacuum solutions, and the boundary conditions at r=0 and the plasma–vacuum interface, the field equations are solved as a two-point boundary-value problem. The numerical methods used are also discussed. Solutions are presented in the form of dispersion curves (plots of vphase vs ω/Ωe) and radial profiles of the field polarizations for the m=±1 modes near electron cyclotron resonance (ECR).