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arXiv · 1608.06755

Optimal laser pulse energy partitioning for air ionization

Elise Schubert·Jean-Gabriel Brisset·Mary Matthews·Antoine Courjaud·Jérôme Kasparian·Jean-Pierre Wolf
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Abstract

We investigate the pulse partitioning of a 6.3 mJ, 450 fs pulse at 1030 nm to produce plasma channels. At such moderate energies, splitting the energy into several sub-pulses reduces the ionization efficiency and thus does not extend the plasma lifetime. We numerically show that when sufficient energy to produce multifilamentation is available, splitting the pulse temporally in a pulse train increases the gas temperature compared to a filament bundle of the same energy. This could improve the mean free path of the free electrons, therefore enhancing the efficiency of discharge triggering.

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Elise Schubert, Jean-Gabriel Brisset, Mary Matthews, Antoine Courjaud, Jérôme Kasparian, Jean-Pierre Wolf. 2016-08-24. Optimal laser pulse energy partitioning for air ionization. https://doi.org/10.1103/physreva.94.033824

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