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arXiv · 0912.0396

Stable laser-driven proton beam acceleration from a two-specie ultra-thin foil

T. P. Yu·A. Pukhov·G. Shvets·M. Chen
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Abstract

By using multi-dimensional particle-in-cell simulation, we present a new regime of stable proton beam acceleration which takes place when a two-specie shaped foil is illuminated by a circularly polarized laser pulse. It is observed that the lighter protons are nearly-instantaneously separated from the heavier carbon ions due to the charge-to-mass ratio difference. The heavy-ions layer extensively expands in space and acts to buffer the proton layer from the Rayleigh-Taylor-like (RT) instability that would have otherwise degraded the proton beam acceleration. A simple three-interface model is formulated to qualitatively explain the stabilization of the light-ions acceleration. Due to the absence of the RT-like instability, the produced high quality mono-energetic proton bunch can be well maintained even after the laser-foil interaction concludes.

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T. P. Yu, A. Pukhov, G. Shvets, M. Chen. 2010-06-24. Stable laser-driven proton beam acceleration from a two-specie ultra-thin foil. https://doi.org/10.1103/physrevlett.105.065002

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