Nonlinear phenomena in helicon plasmas

Abstract

Nonlinear phenomena stimulated by enhanced longitudinal electric field arising near the metal surfaces in helicon plasmas are analyzed theoretically. Ponderomotive effect giving rise to nonlinear instability of the edge plasma, and stochastic electron heating that increases the rf power absorption and plasma generation are considered. Experimental evidences for non-equilibrium electron energy distributions including a population of fast particles with mean energies of the order of a few tens electron-volts are presented.