Optimization of Ion Acceleration by Irradiating Large-Area Suspended Graphene With a Picosecond Laser

Abstract

By irradiating an ultra-thin graphene target, large-area suspended graphene (LSG) with a picosecond and moderate-intensity laser, protons with energies exceeding 100 MeV have been achieved. However, the optimal conditions for ion acceleration in such an atomic-thin target regime using a picosecond intense laser remain unclear. By performing particle-in-cell (PIC) simulations, we discuss optimum conditions to realize energy frontier of laser-driven ion acceleration. Parameter scans over LSG thickness and laser (Formula presented.) -number reveals the optimal conditions under which proton energies exceed 500 MeV. This can be realized with the upgraded laser focus of the LFEX in the future.