Topological structure effects of Laguerre-Gaussian laser on self-collimation acceleration mechanism

Energetic plasma beams can be generated through the interaction between a short-pulse high-intensity laser and solid target. However, obtaining collimated plasma beams with low divergence remains challenging. In this study, we devised a self-collimation scheme driven by a topologically structured Laguerre–Gaussian (LG) laser that irradiates a thin target in three-dimensional particle-in-cell simulations. It was observed that a high-density and narrow plasma beam could be formed by the intrinsic hollow intensity distribution of the LG laser. A magnetic tunnel was generated around the beam and collimated the plasma beam within a radius of hundreds of nanometers. This collimation can be enhanced by increasing the topological charge from l = 1 to l = 3 and then destroyed for a larger l. The collimation method is promising in applications requiring well-collimated energetic plasma beams, such as indirect drive inertial con-finement fusion, laboratory astrophysics, and radiation therapy.