Coupling between surface plasma wave and slow waves supported by an anisotropic conductor

Abstract

A plasma-vacuum interface supports surface plasma wave (SPW) with phase velocity less than the speed of light (v/sub ph/<c). When an anisotropic conductor sheet, separated by a thin dielectric slab is placed on the plasma surface, the SPW couples with the slow wave of the conductor-dielectric structure to give a slow surface plasma wave. The anisotropic conductor is essentially an array of closely spaced thin parallel wires that give electrical conductivity of the structure /spl sigma/=/spl infin/, along the length of the wires and /spl sigma/=0 transverse to it. The field of the slow surface plasma wave decays exponentially in the plasma and in free space above the anisotropic conductor. Inside the dielectric, it can have sinusoidal or exponential variations. The phase velocity of the wave is sensitive to the angle wires make with the direction of wave propagation and to the thickness of the dielectric slab. The slow plasma wave can be excited by a microwave and can sustain large volume plasma, useful for processing of materials.