Low-intensity laser-triggering of rail-gaps with magnesium-aerosol switching-gases

In this paper a new approach to low-intensity laser-triggering of overvolted, gas-insulated spark gaps is demonstrated. The method is based on the addition of Mg-particles with a diameter of about 100 nm to the switching-gas. The spherical particles are suspended in Ar/SF/sub 6/ and N/sub 2//SF/sub 6/ gas mixtures and illuminated by unfocussed nitrogen laser radiation. A laser energy of only a few 100 nJ is required for releasing seed electrons by photoemission from Mg-aerosol particles causing spark-gap ignition with a jitter less than 1 ns.