Skin Effect in Anisotropic Plasmas and Resonance Excitation of Electron-Cyclotron Waves. II. Experiments

The high-frequency magnetic fields within a homogeneous plasma sheath were measured as a function of the plasma parameters and a perpendicularly superimposed static magnetic field. These fields are compared with those calculated taking collision into account. A theoretically predicted resonance of the electron cyclotron wave is observed. Investigations on an electrodeless ring discharge with a superimposed static magnetic field perpendicular to the axis of the discharge also exhibit a similar resonance behavior which in the literature was first reported in 1948. However a valid physical explanation has not been previously established thus far. The phenomenon is widely used to optimize the carrier production in inductively coupled high-frequency ion sources.