Optimization of proton beam quality by obliquely incident laser pre-pulse

Abstract

An investigation has been made to enhance the proton acceleration through the use of an additional obliquely incident lower intense pre-pulse. We observed by means of two-dimensional particle-in-cell simulation that the surface plasma waves can be generated on a flat target using a low-intensity pre-pulse, which is beneficial for enhancing the laser self-focusing and consequently boosting the proton acceleration. We noticed that the proton acceleration is driven by a hybrid acceleration process. The obtained proton beam peak energy and the maximum energy are found to increase by about 205% and 68%, respectively, for the case with pre-pulse in comparison to the cases where the pre-pulse is absent. Moreover, significant degradation of the proton beam energy spread and angular divergence are also seen.