Braenzel J, Andreev A A, Platonov K, Klingsporn M, Ehrentraut L, Sandner W, Schnürer M
Max Born Institute, Max Born Strasse 2A, 12489 Berlin, Germany.
Technical University Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany.
Phys Rev Lett. 2015 Mar 27;114(12):124801. doi: 10.1103/PhysRevLett.114.124801. Epub 2015 Mar 26.
An unprecedented increase of kinetic energy of laser accelerated heavy ions is demonstrated. Ultrathin gold foils have been irradiated by an ultrashort laser pulse at a peak intensity of 8×10^{19} W/ cm^{2}. Highly charged gold ions with kinetic energies up to >200 MeV and a bandwidth limited energy distribution have been reached by using 1.3 J laser energy on target. 1D and 2D particle in cell simulations show how a spatial dependence on the ion's ionization leads to an enhancement of the accelerating electrical field. Our theoretical model considers a spatial distribution of the ionization inside the thin target, leading to a field enhancement for the heavy ions by Coulomb explosion. It is capable of explaining the energy boost of highly charged ions, enabling a higher efficiency for the laser-driven heavy ion acceleration.
已证明激光加速重离子的动能出现了前所未有的增加。用峰值强度为8×10¹⁹W/cm²的超短激光脉冲辐照超薄金箔。通过在靶上使用1.3焦耳的激光能量，已获得动能高达>200兆电子伏且能量分布受带宽限制的高电荷金离子。一维和二维粒子模拟显示了离子电离的空间依赖性如何导致加速电场增强。我们的理论模型考虑了薄靶内电离的空间分布，通过库仑爆炸导致重离子的场增强。它能够解释高电荷离子的能量提升，从而提高激光驱动重离子加速的效率。
