Electrostatic and electromagnetic surface wave theories compared

Abstract

Summary form only given, as follows. The theory of resonance oscillations in a non-uniform thermal plasma and the electrostatic surface wave theory is extended. The new theory is fully electromagnetic. The theory is being used to investigate large area plasma sources and sheath phenomena. For a planar plasma loaded waveguide, the theory predicts two classes of waves. Modes with TE (transverse electric) like field components can be found by solving Maxwell's equations with a non-uniform dielectric given by the local cold plasma dielectric. These modes are unaffected by thermal effects in the limit of this theory. Modes with TM (transverse magnetic) like field components are more complicated-electron inertial and thermal effects allow new quasi-electrostatic (QES) modes to propagate below the peak electron plasma frequency similar to Tonk-Dattner resonances. The wave dispersion predicted by the electromagnetic theory differ from the electrostatic theories for long wavelength surface waves though. This discrepancy is explored. The results illuminate limitations of the electrostatic theories when used to predict phenomena in large area plasma sources.