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arXiv · 0708.2780

Ion dynamics and coherent structure formation following laser pulse self-channeling

Andrea Macchi·Alessandra Bigongiari·Francesco Ceccherini·Fulvio Cornolti·Tatiana V. Liseikina·Marco Borghesi·Satyabrata Kar·Lorenzo Romaganani
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Abstract

The propagation of a superintense laser pulse in an underdense, inhomogeneous plasma has been studied numerically by two-dimensional particle-in-cell simulations on a time scale extending up to several picoseconds. The effects of the ion dynamics following the charge-displacement self-channeling of the laser pulse have been addressed. Radial ion acceleration leads to the ``breaking'' of the plasma channel walls, causing an inversion of the radial space-charge field and the filamentation of the laser pulse. At later times a number of long-lived, quasi-periodic field structures are observed and their dynamics is characterized with high resolution. Inside the plasma channel, a pattern of electric and magnetic fields resembling both soliton- and vortex-like structures is observed.

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Andrea Macchi, Alessandra Bigongiari, Francesco Ceccherini, Fulvio Cornolti, Tatiana V. Liseikina, Marco Borghesi, Satyabrata Kar, Lorenzo Romaganani. 2007-08-21. Ion dynamics and coherent structure formation following laser pulse self-channeling. https://doi.org/10.1088/0741-3335/49/12b/s05

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