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arXiv · 1905.11131

Enhancement of laser-driven ion acceleration in non-periodic nanostructured targets

I. Thiele·J. Ferri·E. Siminos·L. Gremillet·E. Smetanina·A. Dmitriev·G. Cantono·C. -G. Wahlström·T. Fülöp
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Abstract

Using particle-in-cell simulations, we demonstrate an improvement of the target normal sheath acceleration (TNSA) of protons in non-periodically nanostructured targets with micron-scale thickness. Compared to standard flat foils, an increase in the proton cutoff energy by up to a factor of two is observed in foils coated with nanocones or perforated with nanoholes. The latter nano-perforated foils yield the highest enhancement, which we show to be robust over a broad range of foil thicknesses and hole diameters. The improvement of TNSA performance results from more efficient hot-electron generation, caused by a more complex laser-electron interaction geometry and increased effective interaction area and duration. We show that TNSA is optimized for a nanohole distribution of relatively low areal density and that is not required to be periodic, thus relaxing the manufacturing constraints.

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I. Thiele, J. Ferri, E. Siminos, L. Gremillet, E. Smetanina, A. Dmitriev, G. Cantono, C. -G. Wahlström, T. Fülöp. 2019-07-16. Enhancement of laser-driven ion acceleration in non-periodic nanostructured targets. https://arxiv.org/abs/1905.11131

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