Generation of high-current electron beams by a hollow cathode with a ferroelectric plasma source

Abstract

This paper presents results and analysis of an experimental investigation of the operation of a hollow cathode (HC) with an incorporated ferroelectric plasma source (FPS). It was shown that the use of FPS based on a BaTi solid solution allows one to ignite and to sustain a 10 2 -10 3 A HC discharge with duration of 10 �3 -10 �5 s at background pressure of ∼5 × 10 �3 Pa while keeping the HC design with small dimensions. It was found that the development of the HC discharge is accompanied by formation at the surface of the FPS of dense plasma which serves as a powerful (hundreds of kW) pulsed source of current carrying electrons. Parameters of the HC plasma (radial distribution of the plasma density and temperature and plasma potential) for different discharge current amplitudes and two types of FPS are presented. Application of the FPS as an electron source in a diode under an accelerating pulse ≤300 kV and pulse duration ≤400 ns showed that the latter operates in a plasma pre-filled mode with a current amplitude up to 1.6 kA. Parameters of the diode and electron beam for different experimental conditions are presented and discussed.