Excitation Of The L=3 Diocotron Mode In A Pure Electron Plasma By Means Of A Rotating Electric Field

摘要

The l=3 diocotron mode in an electron plasma confined in a Malmberg-Penning trap has been resonantly excited by means of a rotating electric field applied on an azimuthally four-sectored electrode. The experimental observations are interpreted with a theory based on the linearization of the drift-Poisson equations and by means of two-dimensional particle-in-cell simulations. The experimental technique presented in this paper is able to selectively excite different diocotron perturbations and can be efficiently used for electron or positron plasma control and manipulation.