Water dielectric Blumlein-driven fast-electric-discharge KrF laser

A low-impedance water dielectric Blumlein pulse forming network (PFN) with an integral multi-arc-channel initiation switch has been developed as a fast-discharge laser pulser. Preionization of the laser medium is obtained by the use of behind-the-cathode uv arcs driven by an integral low-inductance water capacitor used in conjunction with the main PFN. With KrF, the laser has developed 180 mJ per pulse using a PFN impedance of 1.3 Ω at a laser efficiency of 1.2% from a 70-cm3 extracted volume. In preliminary experiments with a 0.6-Ω PFN, 250 mJ was obtained under similar conditions. The resulting discharge in both cases was extremely homogeneous due to the uniform preionization.