Speaker
Julien Ferri
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P2.2007.pdf
Enhancement of Target Normal Sheath proton acceleration through multi-
pulse laser-target interaction
J.Ferri1, E. Siminos2, T. Fülöp1
1
Department of Physics, Chalmers University of Technology, SE-41296 Göteborg, Sweden
2
Department of Physics, University of Gothenburg, SE-41296 Göteborg, Sweden
Target normal sheath acceleration (TNSA) has been the most commonly used accelerating
method for protons in laser-matter interaction for the past decades, thanks to a relatively
simple experimental implementation. However, even with the continuous increase of the
available laser power, the poor scaling of the maximum energy of the accelerated protons
with the laser energy still constitutes a major drawback for many interesting applications.
Recent experiments proposed to split the energy of the main laser pulse in two pulses,
incident on the target within a short time delay, showing that an increase of the proton
energy and number was possible [1]. Further investigations with careful control of the time
delay between the pulses suggested however that the conditions for such an increase could
be quite specific [2].
In this paper, we describe a slightly modified TNSA scheme, consisting of splitting the main
laser pulse in two pulses of equal energy incident on the target simultaneously, but with
different angles of incidence. Based on 2-dimensional simulations with the EPOCH
Particle-In-Cell code, we show that the multi-pulse interaction that arises leads to an
increase of the peak value of the electric fields and substantial modification of the hot
electron generation process, which leads to a higher hot-electron temperature. This in turn
leads to a strong enhancement of the proton energy (from 8.5 to 14 MeV with a 45 degree
angle and 0.8 J laser) and proton number, and this conclusion remains valid for a large
range of incident angle for the laser pulses.
References
[1] K. Markey et al, Physical Review Letters 105, 195002 (2010)
[2] J. Ferri et al, arXiv:1802.06999 (2018)
