We demonstrate an all-optical method for controlling the transverse motion of an ionization injected electron beam in a laser plasma accelerator by using the transversely asymmetrical plasma wakefield. The laser focus shape can control the distribution of a transversal wakefield. When the laser focus shape is changed from circular to slanted elliptical in the experiment, the electron beam profiles change from an ellipse to three typical shapes. The three-dimensional particle-in-cell simulation result agrees well with the experiment, and it shows that the trajectories of these accelerated electrons change from undulating to helical. Such an all-optical method could be useful for convenient control of the transverse motion of an electron beam, which results in synchrotron radiation from orbit angular momentum.

中文翻译：

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激光等离子体加速器中电离注入电子横向运动的光学控制

我们展示了一种通过使用横向不对称等离子体尾场来控制激光等离子体加速器中电离注入电子束的横向运动的全光学方法。激光焦点形状可以控制横向尾场的分布。当实验中激光焦点形状由圆形变为斜椭圆形时，电子束轮廓由椭圆形变为三种典型形状。三维粒子胞内模拟结果与实验吻合较好，表明这些加速电子的运动轨迹由波浪形变为螺旋形。这种全光学方法可用于方便地控制电子束的横向运动，从而导致来自轨道角动量的同步辐射。