Thermionic emission including both space-charge and image forces

Abstract

The net emission current for a uniform plane thermionic emitter is determined for a range of voltages, temperatures, and various values of the work function. Poisson’s equation is self-consistently solved, using numerical techniques, without any additional phenomenological assumptions. This work accurately specifies the net current in the transition region between space-charge-limited and temperature-limited emission, and we present the first determination of the shape of the interelectrode potential there. A comparison with earlier approximate techniques is also included.