MeV ions can be obtained from laser–foil interactions in the laboratory with the development of ultra-intense laser technology. These energetic ion beams can be applied in fast ignition for inertial confinement fusion, medical therapy, and proton imaging. The ions are mainly accelerated in the laser propagation direction but ion acceleration in an azimuthal orientation was scarcely studied.
Researchers at Shanghai Institute of Optics and Fines Mechanics (SIOM) of Chinese Academy of Sciences used a doughnut Laguerre–Gaussian (LG) laser for the first time to examine laser–plasma interaction in the relativistic intensity regime in three-dimensional particle-in-cell simulations. This study was published on Scientific Reports.
The research demonstrated that a novel rotation of the plasma was produced from the hollow screw-like drill of a LG mode laser. The angular momentum of particles in the longitudinal direction produced by the LG laser was enhanced compared with that produced by the usual laser pulses, such as linearly and circularly polarized Gaussian pulses. The particles could be trapped and uniformly compressed in the dark central minimum of the doughnut LG pulse. The hollow-structured LG laser had potential applications in the generation of x-rays with orbital angular momentum, plasma accelerators, fast ignition for inertial confinement fusion, and pulsars in the astrophysical environment.
This work was supported by the 973 Program the National Natural Science Foundation of China, the International S&T Cooperation Program of China and the Shanghai Natural Science Foundation.
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