Abstract

Spark development is studied by 20-nsec image converter photography. A diffuse and transparent prechannel bridges the gap from the top of the metal vapor jet, which has counterelectrode potential. The prechannel cuts off the development of the cone shaped jet with increasing gap voltage. The final breakdown is initiated by a z-axis, laser induced filament, which expands into the prechannel volume within ≲10 nsec. This interval represents the final high current thermalization phase of the breakdown. Thermal expansion of the initial spark channel (Braginskii) follows.

© 1975 Optical Society of America

Dynamics of the femtosecond laser-triggered spark gap

E. W. Rosenthal, I. Larkin, A. Goffin, T. Produit, M. C. Schroeder, J.-P. Wolf, and H. M. Milchberg
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Expansion of Initial High-Current Spark Channels

Heinz Fischer and C. C. Gallagher
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Electrode Phenomena in a High Current 20-Nanosecond Spark

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Appl. Opt. 6(12) 2176-2178 (1967)

Picosecond laser filament-guided electrical discharges in air at 1 kHz repetition rate

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Explosive Anode Erosion in High Current Sparks

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