Generating collimated high-energy ions by ultra-intense laser pulses interacting with gold cone nanowire target

High-energy collimated ion beam accelerated from ultra-intense laser pulses interacting with gold cone nanowire target (GCNT) was numerically studied and compared with flat target (FT). The 2D PIC (particle-in-cell) simulation results indicate that the gold cone nanowire target demonstrates remarkable improvement in ion beam cutoff energy and collimation efficiency. When the gold cone nanowire target is irradiated by an ultra-intense laser pulse, the laser is effectively focused by the gold cone. Besides, the titled structure of the nanowire can effectively increase the laser–target interaction area. Thereby, the nanowires target can significantly enhance the hot electron yield. Collimated hot electron beams are generated through laser–target interaction, resulting in nearly 500 MG magnetic dipole vortex field generation inside and behind the target. Thus, by effectively suppressing magnetic field Weibel instabilities, collimated ion beam can be generated. These results may provide a reference for fast ignition schemes employing gold cones.