Activation of the explosive-emission cathode under various conditions of preinitiation

• Published in: Vacuum Vol. 143; pp. 473 - 478
• Main Authors: Shunailov, S.A., Yalandin, M.I., Sharypov, K.A., Kolomiets, M.D., Ulmasculov, M.R., Shpak, V.G., Rostov, V.V., Mesyats, G.A.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-09-2017
• Subjects: Cathode; Explosive electrons emission; Field emission; High voltage; Subnanosecond pulse; Field emission; High voltage; Subnanosecond pulse; Explosive electrons emission; Cathode
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/j.vacuum.2017.03.012

Low inertial transition of the field emission into explosive electrons emission at the cathode and related fast-rise-time electron beam formation are of interest in a phase-stable excitation of relativistic high-power microwave oscillators. We present experiments on the cathode activation using emission initiation during specially prepared advance voltage pulse (prepulse) possessing variable amplitude of tens-hundreds kilovolts and the width adjustable from tenths to units of nanosecond. Such a prepulse can be separated in time with a main accelerating pulse as well as adjoined to the fast-rise-time voltage front.
•Formation of synchronized high-voltage subnanosecond pulses.•Dynamic time-domain reflecrometry in high-current electronics.•Control of explosive electron emission by advanced voltage pulses.•Recovery of cold-cathode emissivity by the train of voltage pulses.