Plasma physical model of the photoconductively switched spark gap

摘要

In this contribution, we will present a plasmaphysical model of a photoconductively switched spark gap. Our aim is to gain physical insight into the operation of this device, in particular in the current rise time and the Ohmic dissipation losses in the spark gap. To this end, two separate models have been made: a simple, analytical model of the cathode fall and a complex, numerical model of the conductive arc. The qualitative agreement between the models and experimental results is satisfactory. The models suggest that rise time of the arc conductivity is much longer than the formation time of the cathode fall and therefore determines the switching time.