论文标题
用于等离子韦克菲尔德的极化电子加速器的自旋滤波器
A spin-filter for polarized electron acceleration in plasma wakefields
论文作者
论文摘要
我们提出了一种滤波器方法，以产生来自气泡和吹风尾菲尔德加速器的高极化的电子光束。该机制是基于识别所有具有低极化的电子梁亚集的想法，并通过放置在等离子体加速器后面的X形缝隙过滤掉它们。为了找到这些子集，我们研究了捕获过程中初始方位角角与单电子的自旋之间的依赖性。这种依赖性表明，如果最初平行或平行于局部磁场，横电子旋转在注入过程中保留其方向。我们得出了局部束极化的精确相关性，这是坐标和电子相角的函数。结合经典自旋动力学的三维粒子中的粒子模拟表明，旋转过滤后可以将光束极化从35％增加到约80％。注入的通量非常限制以保留梁极化，例如<参考文献[27]中的1KA。通过采用提出的滤波器机制来消除此限制。讨论了该方法的鲁棒，其中包含驱动束波动，抖动，滤波器的厚度和初始温度。这个想法标志着一种基于韦克菲尔德加速的高效且简单的策略，以产生能量的极化电子束
We propose a filter method to generate electron beams of high polarization from bubble and blow-out wakefield accelerators. The mechanism is based on the idea to identify all electron-beam subsets with low-polarization and to filter them out by an X-shaped slit placed right behind the plasma accelerator. To find these subsets we investigate the dependence between the initial azimuthal angle and the spin of single electrons during the trapping process. This dependence shows that transverse electron spins preserve their orientation during injection if they are initially aligned parallel or anti-parallel to the local magnetic field. We derive a precise correlation of the local beam polarization as a function of the coordinate and the electron phase angle. Three-dimensional particle-in-cell simulations, incorporating classical spin dynamics, show that the beam polarization can be increased from 35% to about 80% after spin filtering. The injected flux is strongly restricted to preserve the beam polarization, e.g. <1kA in Ref.[27]. This limitation is removed by employing the proposed filter mechanism. The robust of the method is discussed that contains drive beam fluctuations, jitters, the thickness of the filter and initial temperature. This idea marks an efficient and simple strategy to generate energetic polarized electron beams based on wakefield acceleration
