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  • Letter
  • Open Access

Spin inertia as a source of topological magnons: Chiral edge states from coupled precession and nutation

Subhadip Ghosh1,*, Mikhail Cherkasskii2, Ritwik Mondal1, Alexander Mook3, and Levente Rózsa4,5,†

  • *Contact author: 22dr0226@iitism.ac.in
  • †Contact author: rozsa.levente@wigner.hun-ren.hu
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Phys. Rev. Research 8, L032040 – Published 3 September, 2026

DOI: https://doi.org/10.1103/7njs-vyl9

Abstract

Spin inertia has been demonstrated to give rise to high-frequency nutational excitations beyond the conventional low-frequency precessional modes. Here, we demonstrate that the hybridization between precessional and nutational magnons may give rise to topological phenomena in the spin-wave spectrum. This hybridization requires the presence of interactions breaking angular-momentum conservation, such as the pseudodipolar interaction. We show on the example of a honeycomb ferromagnet how topological gaps open between the precessional and nutational bands that host chiral edge states in slab geometries. Our work establishes a theoretical foundation for exploring inertial spin dynamics as a route to engineer topological phases in magnetic materials.

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Phys. Rev. Research 8, L032040– Published 3 September, 2026
  • Received 27 March 2026
  • Accepted 31 July 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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