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Surface Oscillations in Overdense Plasmas Irradiated by Ultrashort Laser Pulses

A. Macchi·F. Cornolti·F. Pegoraro·T. V. Liseikina·H. Ruhl·V. A. Vshivkov
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Abstract

The generation of electron surface oscillations in overdense plasmas irradiated at normal incidence by an intense laser pulse is investigated. Two-dimensional (2D) particle-in-cell simulations show a transition from a planar, electrostatic oscillation at $2ω$, with $ω$ the laser frequency, to a 2D electromagnetic oscillation at frequency $ω$ and wavevector $k>ω/c$. A new electron parametric instability, involving the decay of a 1D electrostatic oscillation into two surface waves, is introduced to explain the basic features of the 2D oscillations. This effect leads to the rippling of the plasma surface within a few laser cycles, and is likely to have a strong impact on laser interaction with solid targets.

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A. Macchi, F. Cornolti, F. Pegoraro, T. V. Liseikina, H. Ruhl, V. A. Vshivkov. 2001-10-29. Surface Oscillations in Overdense Plasmas Irradiated by Ultrashort Laser Pulses. https://doi.org/10.1103/physrevlett.87.205004

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