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arXiv · 1610.01301

Stimulated Raman scattering in the relativistic regime in near-critical plasmas

J. G. Moreau·E. d'Humières·R. Nuter·V. T. Tikhonchuk
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Abstract

Interaction of a high intensity short laser pulse with near-critical plasmas allows to achieve extremely high coupling efficiency and transfer laser energy to energetic ions. One dimensional Particle-In-Cell (PIC) simulations are considered to detail the processes involved in the energy transfer. A confrontation of the numerical results with the theory highlights a key role played by the process of stimulated Raman scattering in the relativistic regime. The interaction of a 1 ps laser pulse (I $\sim$ 6.10$^{18}$ W.cm$^2$) with an under-critical (0.5 $n_c$) homogeneous plasma leads to a very high plasma absorption reaching 68 % of the laser pulse energy. This permits a homogeneous electron heating all along the plasma and an efficient ion acceleration at the plasma edges and in cavities.

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J. G. Moreau, E. d'Humières, R. Nuter, V. T. Tikhonchuk. 2016-10-05. Stimulated Raman scattering in the relativistic regime in near-critical plasmas. https://doi.org/10.1103/physreve.95.013208

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