Weichman K, Santos J J, Fujioka S, Toncian T, Arefiev A V
Department of Mechanical and Aerospace Engineering, University of California at San Diego, La Jolla, CA, 92093, USA.
University of Bordeaux, CNRS, CEA, CELIA, UMR 5107, 33405, Talence, France.
Sci Rep. 2020 Nov 3;10(1):18966. doi: 10.1038/s41598-020-75915-8.
We present the first 3D fully kinetic simulations of laser driven sheath-based ion acceleration with a kilotesla-level applied magnetic field. The application of a strong magnetic field significantly and beneficially alters sheath based ion acceleration and creates two distinct stages in the acceleration process associated with the time-evolving magnetization of the hot electron sheath. The first stage delivers dramatically enhanced acceleration, and the second reverses the typical outward-directed topology of the sheath electric field into a focusing configuration. The net result is a focusing, magnetic field-directed ion source of multiple species with strongly enhanced energy and number. The predicted improvements in ion source characteristics are desirable for applications and suggest a route to experimentally confirm magnetization-related effects in the high energy density regime. We additionally perform a comparison between 2D and 3D simulation geometry, on which basis we predict the feasibility of observing magnetic field effects under experimentally relevant conditions.
我们展示了在施加千特斯拉级磁场的情况下，基于激光驱动鞘层的离子加速的首个三维全动力学模拟。强磁场的应用显著且有益地改变了基于鞘层的离子加速，并在与热电子鞘层随时间演化的磁化相关的加速过程中产生了两个不同阶段。第一阶段实现了显著增强的加速，第二阶段则将鞘层电场典型的向外拓扑结构转变为聚焦构型。最终结果是形成了一个聚焦的、磁场导向的多物种离子源，其能量和数量都得到了极大增强。离子源特性的预测改进对于应用而言是可取的，并为在高能量密度 regime 中通过实验证实与磁化相关的效应提供了一条途径。我们还对二维和三维模拟几何结构进行了比较，在此基础上预测了在实验相关条件下观察磁场效应的可行性。
