Enhanced laser driven ion acceleration by using an Al-DLC double layer target

Abstract

In this paper, the acceleration of protons, carbon and Aluminum ions during the interaction of a laser pulse in two different relativistic intensity ranges of I=6.4×1019 W/cm2 and I=6.8×1021 W/cm2 (for λ = 1 μm equal to normalized amplitudes of a = 5 and a = 50 respectively) with solid density targets are investigated numerically. The interaction of laser pulse with a thin DLC layer as the first target and a double layer target consists of an extra layer of mid-z Al element in front of the DLC layer as the second one is considered. The main focus of this study is on the acceleration process at early time of the interaction by the electrostatic shock field created in front of the thin foil and the radiation pressure acceleration regime at the end of the interaction. The ability of this suggestion is simulated by 1D-3 V particle in cell (PIC) code. Simulation results indicate that Al ions of the extra layer create stronger shock field in front of the target. So that participating ions of the double layer target in the acceleration process which are reflected from this powerful field, gain considerable energy about 400 MeV/u for lower laser pulse intensity (a = 5) and 680 MeV/u for higher laser pulse intensity (a = 50) with the monoenergetic energy distributions by energy spreading less than %4. This amount of energy for protons and carbon ions is much more than the pure DLC layer. This result reveals Al ions can reach to tens of GeV energy scale at the end of the interaction.