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arXiv · 2501.01201

A Magnon Band Analysis of GdRu2Si2 in the Field-Polarized State

G. D. A. Wood·J. R. Stewart·D. A. Mayoh·J. A. M. Paddison·J. Bouaziz·S. M. Tobin·O. A. Petrenko·M. R. Lees·P. Manuel·J. B. Staunton·G. Balakrishnan
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Abstract

Understanding the formation of skyrmions in centrosymmetric materials is a problem of fundamental and technological interest. GdRu2Si2 is one such candidate material which has been shown to host a variety of multi-Q magnetic structures, including in zero-field. Here, inelastic neutron scattering is used to measure the spin excitations in the field-polarized phase of GdRu2Si2. Linear spin wave theory and a method of interaction invariant path analysis are used to derive a Hamiltonian accounting for the observed spectra, and comparisons to \textit{ab initio} calculations are made. No evidence for anisotropic or higher order-exchange terms beyond bilinear Heisenberg exchange is found. This is discussed in the context of the multi-Q states existing at lower fields, for which these types of terms have previously been conceived to be significant in the formation of multi-Q ground states.

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G. D. A. Wood, J. R. Stewart, D. A. Mayoh, J. A. M. Paddison, J. Bouaziz, S. M. Tobin, O. A. Petrenko, M. R. Lees, P. Manuel, J. B. Staunton, G. Balakrishnan. 2025-01-02. A Magnon Band Analysis of GdRu2Si2 in the Field-Polarized State. https://doi.org/10.1038/s41535-025-00755-6

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