Title :
Vacuum breakdown on metal surfaces
Author :
Schwirzke, Fred R.
Author_Institution :
Dept. of Phys., US Naval Postgrad. Sch., Monterey, CA, USA
fDate :
10/1/1991 12:00:00 AM
Abstract :
The unipolar arc model is described. Experimental proof that unipolar arcing represents a discharge form which easily leads to explosive plasma formation is provided. Using a laser-produced plasma, it has been demonstrated that unipolar arcs ignite and burn on a nanosecond time scale without any external electric field being applied. Similar unipolar arc craters have been observed on the cathode surface of a pulsed vacuum diode with an externally applied field of 0.5 MV/cm. The experimental results show that cathode spots are formed by unipolar arching. The localized buildup of plasma above an electron-emitting spot naturally leads to a pressure gradient and electric field distribution which drives the unipolar arc. The high current density of a unipolar arc provides explosive plasma formation
Keywords :
arcs (electric); discharges (electric); electric breakdown of solids; ignition; plasma production; burning; cathode spots; cathode surface; craters; electric field distribution; electron-emitting spot; explosive plasma formation; ignition; laser-produced plasma; metal surfaces; pressure gradient; pulsed vacuum diode; unipolar arc model; vacuum breakdown; Cathodes; Current density; Diodes; Drives; Explosives; Laser modes; Plasma density; Surface discharges; Vacuum arcs; Vacuum breakdown;
Journal_Title :
Plasma Science, IEEE Transactions on
