journal article·2025-04-16Open access

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

npj Quantum Materials· Volume 10· Issue 1

Abstract

Abstract Understanding the formation of skyrmions in centrosymmetric materials is a problem of fundamental and technological interest. GdRu2Si2 is a candidate material that hosts a variety of multi-Q magnetic phases, 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 spectra. The Hamiltonian, dominated by bilinear (Ruderman-Kittel-Kasuya-Yosida) Heisenberg exchange, compares favorably to ab initio calculations. Dipolar interactions are a secondary energy scale to consider, with J D.D~ 0.05J RKKY. However, it is shown that in the field-polarized phase the dipolar interactions ‘self screen’ so that their effect is largely suppressed. No specific evidence for higher-order exchange is found. These aspects are discussed in the context of the lower field multi-Q states and the anisotropy of the system.
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Research context

OpenAlex topics: Rare-earth and actinide compounds · Advanced Condensed Matter Physics · Magnetic and transport properties of perovskites and related materials

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