Compact Marx generator in air triggered by femtosecond filaments

We present results of an experimental study aimed at producing a compact Marx generator consisting of three to six stages in series. A continuous plasma column is used to trigger simultaneously each element of the generator. This plasma channel is created by the filamentation of an intense femtosecond laser pulse (200-250 mJ, 700 fs @ 800 nm) from a Ti: Sapphire chirped pulse amplification laser chain. After propagation in air, the weakly converging laser beam undergoes multiple filamentation, leading to the production of a 1-2 m long continuous plasma column of diameter ~5 mm which connects quasi instantaneously the gap switches of all Marx generator stages.