Steady states stability features of the electron–positron plasma diode

Abstract

Stationary states stability features of a planar geometry diode with electron and positron counter flows are studied. Such a diode may be considered as a model to elucidate the nature of the pulsar radio emission. The equation for the electric field perturbation amplitude is derived. The exact solution of this equation for the homogeneous stationary field is found. On the basis of the plasma dispersion relation, the stability threshold in terms of the electron current density is found above which the stationary solutions become unstable. This threshold turned out to be [Formula: see text] times higher than the known Pierce threshold. It can be expected that the development of the detected instability will lead to the electric field oscillations that induce electromagnetic radiation.