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Spin-caloritronic signatures of soft magnons in bilayer CrSBr

Rob den Teuling1,*, Ping Tang2, Gerrit E. W. Bauer2, and Yaroslav M. Blanter1

  • *Contact author: r.denteuling@tudelft.nl
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Phys. Rev. B 114, 214415 – Published 15 October, 2026

DOI: https://doi.org/10.1103/ckf6-gwfq

Abstract

Spin transport in magnetic insulators is often treated by assuming that magnons carry a fixed spin angular momentum of ℏ, which does not hold in general, however. Here, we calculate the magnon spin angular momentum of a layered antiferromagnet as a function of applied magnetic field and wave vector. We show that the triaxial anisotropy and intralayer dipolar interactions in bilayer CrSBr renormalize the magnon spin angular momentum, which diverges upon field-induced magnon softening. This divergence gives rise to a pronounced peak in the thermal spin Seebeck response and provides a clear spin-caloritronic signature of soft magnons.

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Outline

Information

Phys. Rev. B 114, 214415– Published 15 October, 2026
  • Received 26 May 2026
  • Revised 25 August 2026
  • Accepted 21 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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