Figure 5
From: Enhancing laser-driven proton acceleration by using micro-pillar arrays at high drive energy
The PIC simulation follows the evolution of the spatial distribution of hot electrons (E > 100 keV) at (a) −450 fs, (b) −250 fs and (c) 0 fs with respect to the time when the pulse peak (a o = 1.2) reaches the film layer. As the laser pulse moves forward into the pillar array, further energetic electrons are generated and an acceleration sheath field (red curve) builds up in the pillar direction. (d) At the time of the laser peak, this electric field extends differently behind the film for a planar target (blue empty squares) compared to a pillar array (red solid squares).
