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arXiv · 0811.1736

Efficient Raman amplification into the PetaWatt regime

R. M. G. M. Trines·F. Fiúza·R. Bingham·R. A. Fonseca·L. O. Silva·R. A. Cairns·P. A. Norreys
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Abstract

Raman amplification of a short laser pulse off a long laser beam has been demonstrated successfully for moderate probe intensities ($\sim 10^{16}$ W/cm$^2$) and widths ($\sim 50$ micron). However, truly competitive intensities can only be reached if the amplification process is carried out at much higher probe intensities ($10^{17}-10^{18}$ W/cm$^2$ after amplification) and widths (1-10 mm). In this paper we examine the opportunities and challenges provided by this regime through the first 2-dimensional particle-in-cell simulations using wide pulses. A parameter window is identified in which a 10 TW, 600 $μ$m wide, 25 ps long laser pulse can be efficiently amplified to 2 PW peak intensity.

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R. M. G. M. Trines, F. Fiúza, R. Bingham, R. A. Fonseca, L. O. Silva, R. A. Cairns, P. A. Norreys. 2009-01-09. Efficient Raman amplification into the PetaWatt regime. https://arxiv.org/abs/0811.1736

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