Ion Acceleration from Near-Critical-Density Plasmas via Magnetic Vortex Acceleration in 3D Particle-in-cell Simulations*

We explored laser-driven ion acceleration via the Magnetic Vortex Acceleration scheme using 3D Warp+PICSAR and WarpX PIC simulation codes. In this scheme a high intensity and short pulse laser pulse propagates in near critical density plasma targets, making a channel in both electron and ion density. When the laser pulse exits the plasma, it establishes strong longitudinal electric fields that can accelerate the ions, which are pinched by the electrons in a thin filament along the laser propagation axis.  We found that under the optimum conditions of the target thickness and density [1], the maximum ion energy in 3D is about 50% lower than that in 2D due to the smaller channel size in 3D. Particle tracking method is used to understand the acceleration process in more detail.  [1] S. S. Bulanov, et al, Phys. Plasmas 17,043105(2010)