近日，西安交通大学的栗建兴及其研究团队取得一项新进展。经过不懈努力，他们揭示外激光场中的相对论涡旋电子动力学。相关研究成果已于2024年11月7日在国际知名学术期刊《物理评论A》上发表。

在这项工作中，该研究团队系统地探讨了，相对论涡旋电子与线偏振（LP）和圆偏振（CP）激光脉冲，及其叠加态在迎面碰撞过程中的动力学行为。研究人员构建了一个基于Volkov-Bessel波函数的理论框架，用以描述涡旋电子在这些外场中的时空特性。

研究结果表明，涡旋电子束的中心遵循点电荷电子的经典轨迹，同时保持了涡旋本征态和叠加态的横向结构。具体而言，圆偏振激光脉冲会使电子束中心发生旋转，而线偏振激光脉冲则会导致其发生横向偏移。在包含两种模式的场中，线偏振和圆偏振激光脉冲的联合作用会使电子束呈现出扭曲的螺旋图案。

这项研究发现展示了利用不同激光模式对涡旋电子束进行灵活控制的潜力，为未来实验和理论研究奠定了基础。本研究为利用更真实的激光或其他类型外场操控涡旋电子束的研究，提供了基准参考。

据悉，研究涡旋电子与电磁场的相互作用，对于推动粒子加速技术、背景场中的散射理论，以及开发用于材料诊断的新型电子束至关重要。

附：英文原文

Title: Dynamics of relativistic vortex electrons in external laser fields

Author: Mamutjan Ababekri, Yu Wang, Ren-Tong Guo, Zhong-Peng Li, Jian-Xing Li

Issue&Volume: 2024/11/07

Abstract: Investigating the interactions of vortex electrons with electromagnetic fields is crucial for advancing particle acceleration techniques, scattering theory in background fields, and developing novel electron beams for material diagnostics. In this work, we systematically study the dynamics of relativistic vortex electrons during their head-on collisions with linearly polarized (LP) and circularly polarized (CP) laser pulses, as well as their superposition. We develop a theoretical framework using Volkov-Bessel wave functions to describe the spatiotemporal characteristics of vortex electrons in these external fields. We show that the beam center of the vortex electron follows the classical trajectory of a point-charge electron while maintaining the transverse structure of both vortex eigenstates and superposition states. Specifically, CP laser pulses cause the beam center to rotate, while LP laser pulses induce a lateral shift. The combined effect of LP and CP laser pulses in a two-mode field results in a twisted spiral pattern. Our findings demonstrate the potential for versatile control of vortex electron beams using various laser modes, providing a foundation for future experimental and theoretical studies. This work serves as a benchmark reference for investigations into the manipulation of vortex electron beams using more realistic laser or other types of external fields.

DOI: 10.1103/PhysRevA.110.052207

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.110.052207