Mechanisms Affecting Long Conduction Time Plasma Opening Switches

Experimental evidence suggests that long conduction time (≥ 1 μs) plasma opening switches open more slowly than expected on the basis of magnetic forces, and perhaps even on the basis of plasma erosion. The fastest opening mechanism should prevail, and in large current (≥ .5 MA) long conduction times applications this is the J x B force. We propose that the slow opening is associated with charge exchange with and/ or electron ionization of neutral particles produced in the switch gap during and/or prior to the power pulse. The possibility of such mechanisms bears on the choice of switch plasma and on surface conditioning procedures in the development of fast opening switch technology.