Experimental investigation on a long-conduction time-plasma opening switch and its application on a 0.1 TW generator for prepulse suppression

The authors discuss their work on plasma opening switches (POSs). After characterization of the plasma created by plasma guns, physical processes occurring during long-conduction-time POS operation are investigated using diagnostics such as Rogowski coils, Faraday cups, and time-integrated and streak photographs. The importance of different parameters of the authors´ system, such as the generator charging voltage, the geometry of the switch, and the plasma density, are studied. The authors´ results are correlated with two theoretical models. The experiment shows that the use of an 80% transparent inner electrode can significantly increase the opening speed. The POS is applied in a short-conduction-time experiment. Results obtained in upgrading of a 0.1-TW generator (2 Ω, ~250 kA, ~50 ns) are presented. Prepulse suppression is achieved with a short-circuit load and with an aluminum vapor Z-pinch as a load. Incorporation of the POS improves the compression of the Z-pinch and increases the radiation yield