D. Khaghani,
M. Lobet,
B. Borm,
L. Burr,
F. Gärtner,
L. Gremillet,
L. Movsesyan,
O. Rosmej,
M. Toimil-Molares,
F. Wagner,
and P. Neumayer
Enhancing laser-driven proton acceleration by using micro-pillar arrays at high drive energy
Sci. Rep., 7 :11366 (September 2017)
Enhancing laser-driven proton acceleration by using micro-pillar arrays at high drive energy
Sci. Rep., 7 :11366 (September 2017)
Abstract:
The interaction of micro- and nano-structured target surfaces with high-power laser pulses is being widely investigated for its unprecedented absorption efficiency. We have developed vertically aligned metallic micro-pillar arrays for laser-driven proton acceleration experiments. We demonstrate that such targets help strengthen interaction mechanisms when irradiated with high-energy-class laser pulses of intensities ~10^17–18 W/cm2. In comparison with standard planar targets, we witness strongly enhanced hot-electron production and proton acceleration both in terms of maximum energies and particle numbers. Supporting our experimental results, two-dimensional particle-in-cell simulations show an increase in laser energy conversion into hot electrons, leading to stronger acceleration fields. This opens a window of opportunity for further improvements of laser-driven ion acceleration systems.