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arXiv · 2607.22315

Robustness of Off-Axis Electron Vortices in Nonuniform Magnetic Fields

Hui-Dong Huang·Qi Meng·Zhi-Bin Wang·Liang Lu·Jian Chen·Li-Ping Zou
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Abstract

Rotational symmetry protects the topological charge of on-axis electron vortices but not of off-axis vortices. We identify an additional SU(1,1) dynamical invariant that guarantees conservation of their intrinsic orbital angular momentum within the near-axis approximation. First-principles simulations of an off-axis electron vortex traversing a Glaser lens confirm this prediction, establishing a robust transport mechanism in axisymmetric nonuniform magnetic fields.

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Hui-Dong Huang, Qi Meng, Zhi-Bin Wang, Liang Lu, Jian Chen, Li-Ping Zou. 2026-07-24. Robustness of Off-Axis Electron Vortices in Nonuniform Magnetic Fields. https://arxiv.org/abs/2607.22315

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