Electron Injection and Beam Dynamics in a Laser Wakefield Acceleration Driven by Laser Pulses Carrying Orbital Angular Momentum

Q. Qian; M. Li; Y. Ma; P. T. Campbell; C-H. Chang; E. Denis; N. Ernst; R. Fedosejevs; B. Hou; A. James; M. W. von der Leyen; K. Krushelnick; C. Kuranz; A. Longman; A. Maksimchuk; J. Nees; P. Norreys; T. Nutting; J. B. Ohland; J. Palastro; A. G. R. Thomas; R. Timmis; L. Willingale; M. Burger

arXiv · 2608.15039

Electron Injection and Beam Dynamics in a Laser Wakefield Acceleration Driven by Laser Pulses Carrying Orbital Angular Momentum

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Abstract

Laser pulses carrying orbital angular momentum (OAM) provide a new degree of freedom for controlling plasma-based accelerators. Here, we demonstrate experimentally laser wakefield acceler- ation driven by OAM laser pulses, producing electron beams with distinct broad-band energy spectra and angularly structured phase space. The measured spectra exhibit a two-beamlet structure with correlated angular dispersion, indicating injection occurring at multiple azimuthal phases of the plasma wake. Particle-in-cell simulations reproduced the observed spectral features and revealed helical electron trajectories driven by the OAM-induced wakefields. These results show that the phase structure of the laser driver can shape electron injection and acceleration dynamics, opening a route toward optimal control of beam structure in compact laser-driven accelerators.

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Q. Qian, M. Li, Y. Ma, P. T. Campbell, C-H. Chang, E. Denis, N. Ernst, R. Fedosejevs, B. Hou, A. James, M. W. von der Leyen, K. Krushelnick, C. Kuranz, A. Longman, A. Maksimchuk, J. Nees, P. Norreys, T. Nutting, J. B. Ohland, J. Palastro, A. G. R. Thomas, R. Timmis, L. Willingale, M. Burger. 2026-08-15. Electron Injection and Beam Dynamics in a Laser Wakefield Acceleration Driven by Laser Pulses Carrying Orbital Angular Momentum. https://arxiv.org/abs/2608.15039

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