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arXiv · 2511.00174

Observation of Ion-wave Satellites to Laser Harmonics in Intense Picosecond Laser-Solid Interaction

R. S. Marjoribanks·L. Zhao·F. W. Budnik·G. Kulcsar·R. Wagner·D. Umstadter·R. P. Drake·M. C. Downer
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Abstract

Detailed spectra of harmonics produced from ultra-intense, sub-picosecond, high-contrast laser pulses incident on solid targets have shown the first observation of regular red- and blue-shifted satellites. Their frequency shift is slightly less than the frequency of a nominal, pure ion-plasma wave associated with electron critical density, where an ion-acoustic wave would be expected. We explain this as the result of a substantial reduction of Debye shielding as the intense optical fields compete to drive electrons in large-amplitude oscillations. This general effect leads to a larger, dynamical and anisotropic Debye length, which should have a broad impact on plasma physics in this regime.

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R. S. Marjoribanks, L. Zhao, F. W. Budnik, G. Kulcsar, R. Wagner, D. Umstadter, R. P. Drake, M. C. Downer. 2025-10-31. Observation of Ion-wave Satellites to Laser Harmonics in Intense Picosecond Laser-Solid Interaction. https://arxiv.org/abs/2511.00174

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