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arXiv · 2608.28301

Wakefield-Dressed Relativistic Vortex Electrons in Plasma Accelerators

Zhigang Bu·Lingang Zhang·Liangliang Ji
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Abstract

Plasma wakefield acceleration is usually regarded as a classical mechanism for producing high- energy charged-particle beams. Here we show that an axisymmetric plasma wakefield can also act as a moving quantum structure that supports relativistic vortex electron states. Starting from the Dirac equation, we derive the electron spinor eigenstates with definite total angular momentum in an ideal bubble-regime wakefield. The transverse focusing field confines and quantizes the electron transverse motion into Laguerre-Gaussian vortex modes, while the longitudinal electric field acceler- ates the electron without destroying the symmetry-protected angular momenta. We further analyze the localized and off-axis vortex electron wave-packets, and non-ideal wakefield perturbations, and identify the conditions for preserving electron-vortex-state purity. These results suggest plasma wakefield as a route toward high-energy vortex electrons and extend plasma-based acceleration from classical beam dynamics to quantum-state control of relativistic particles.

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Zhigang Bu, Lingang Zhang, Liangliang Ji. 2026-08-28. Wakefield-Dressed Relativistic Vortex Electrons in Plasma Accelerators. https://arxiv.org/abs/2608.28301

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