Particle-in-cell simulations of collisionless perpendicular shocks driven at a laser-plasma device

Experiments of generation of quasi-perpendicular collisionless shocks driven by laser plasma were performed at the Shenguang-II laser facility with intense lasers. Here, using 1D a particle-in-cell simulation code including protons, carbon ions, and electrons, we investigate the experimental shock formation via the interaction between the laser-ablated piston and ambient plasma magnetized by a large pre-existing magnetic field and the associated ion dynamics in more detail. Simulation results show that, given enough time and space, ambient protons and carbon ions can be reflected at the piston-ambient interface successively, which leads to the formation of corresponding shocks before the piston and interface. Electric fields associated with the initial interaction known as Larmor coupling and the shocks may accelerate ambient protons, carbon ions reflected at the interface or shocks, and piston ones transmitted to the ambient region before shock formation.