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arXiv · 2102.12657

Generation of Radio Frequency Radiation by Femtosecond Filaments

Travis Garrett·Jennifer Elle·Michael White·Remington Reid·Alexander Englesbe·Ryan Phillips·Peter Mardahl·Erin Thornton·James Wymer·Anna Janicek·Oliver Sale·Andreas Schmitt-Sody
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Abstract

Recent experiments have shown that femtosecond filamentation plasmas generate ultra-broadband radio frequency radiation (RF). We show that a combination of plasma dynamics is responsible for the RF: a plasma wake field develops behind the laser pulse, and this wake excites (and copropagates with) a surface wave on the plasma column. The surface wave proceeds to detach from the end of the plasma and propagates forward as the RF pulse. We have developed a four stage model of these plasma wake surface waves and find that it accurately predicts the RF from a wide range of experiments, including both 800 nm and 3.9 $\mu$m laser systems.

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Travis Garrett, Jennifer Elle, Michael White, Remington Reid, Alexander Englesbe, Ryan Phillips, Peter Mardahl, Erin Thornton, James Wymer, Anna Janicek, Oliver Sale, Andreas Schmitt-Sody. 2021-02-25. Generation of Radio Frequency Radiation by Femtosecond Filaments. https://doi.org/10.1103/physreve.104.l063201

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