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  • Open Access

Arbitrary-velocity Volkov wave packets

D. Ramsey*, J. McKeown, and J. P. Palastro

  • *Contact author: dram@lle.rochester.edu
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Phys. Rev. Research 8, 033322 – Published 15 September, 2026

DOI: https://doi.org/10.1103/9fc9-tmkm

Abstract

The evolution of a charged lepton in the field of an electromagnetic plane wave can be described as a superposition of Volkov states. Here, we demonstrate that imposing specific momentum correlations among Volkov states produces a spatiotemporally structured wave packet whose probability-density peak, evaluated on fixed-light-cone slices, travels at an arbitrary tailored velocity. This velocity can be chosen independently of both the field amplitude and the velocity expectation value. The imposed momentum correlations modify the expectation-value trajectory, providing a measurable signature of the arbitrary velocity within a physical observable.

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Outline

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Phys. Rev. Research 8, 033322– Published 15 September, 2026
  • Received 14 April 2026
  • Accepted 8 August 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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