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Space-time electron wave packets with tunable skyrmion textures

Sharoz Schezwen

Yijie Shen*

  • Centre of Disruptive Photonics Technologies, School of Physical and Mathematical Sciences, Singapore and School of Electrical and Electronics Engineering, Nanyang Technological University, Singapore

  • *Contact author: yijie.shen@ntu.edu.sg
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APS Open Sci. 1, 000163 – Published 7 October, 2026

DOI: https://doi.org/10.1103/pnvl-7bx7

Abstract

Space-time wave packets (STWPs) have enabled numerous nontrivial properties, such as tunable group velocities, nondiffraction, and nonlocal spin textures in optical fields. However, this has not been properly studied in matter waves. Here, we investigate free-electron STWPs, which are propagation-invariant and group-velocity-tunable matter wave packets, constructed by constraining the spatiotemporal spectrum of the electron wavefunction in momentum space. Due to the unique dispersion of free electrons, the electron STWP can carry two different topologies and host both meron and skyrmion topological textures in momentum space. We demonstrate the topological phase transitions and tunable skyrmion numbers by spectral geometry tuning. We also show the topologically robust propagation of the electron pulses and corresponding real-space skyrmionic expectation value textures encoded within each single electron wavefunction. Our results open a platform for topological free-electron wave packets uses in sensing and information transfer.

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APS Open Sci. 1, 000163– Published 7 October, 2026
Vol. 1
  • Received 2 July 2026
  • Accepted 9 September 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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