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Ratchet motion of magnetic skyrmions driven by surface acoustic sawtooth waves

Philipp Schwenke*, Ephraim Spindler, Vitaliy I. Vasyuchka, Alexandre Abbass Hamadeh, Philipp Pirro, and Mathias Weiler

  • *Contact author: philipp.schwenke@rptu.de
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Phys. Rev. B 112, 214409 – Published 4 December, 2025

DOI: https://doi.org/10.1103/w75m-hlsr

Abstract

The manipulation of skyrmions by surface acoustic waves (SAWs) has garnered significant interest in the field of spintronic devices. Previous studies established that skyrmions can be generated and moved by strain pulses. In this study, we propose that sawtooth-SAWs can be used to drive a ratchet motion of magnetic skyrmions in the presence of pinning centers. This results in a net motion of the skyrmions orthogonal to the continuously applied SAW. The ratchet motion is fundamentally caused by nonvanishing pinning, so that a certain strain gradient magnitude is required to overcome pinning and start skyrmion motion. We demonstrate the feasibility of our concept by micromagnetic simulations and analytical model calculations.

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Phys. Rev. B 112, 214409– Published 4 December, 2025
  • Received 13 March 2025
  • Revised 30 October 2025
  • Accepted 12 November 2025
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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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