Fundamental processes in laser-triggered electrical breakdown of gases

Abstract

The authors describe the results of an experimental study of the physical mechanisms important for laser triggering of spark gaps in the longitudinal, striking-electrode geometry. The authors present clear, new evidence for the propagation of a streamer in under-volted gaps, and for the interaction of the triggering laser with the streamer head. They find that the propagation conditions of the initial streamer markedly affect the subsequent heating of the incipient channel to form the spark. A model of the laser-triggered breakdown process based on these results is presented and discussed.