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arXiv · 2305.05497

Magnon dispersion in ferromagnetic SrRuO$_3$

K. Jenni·S. Kunkemöller·A. Tewari·R. A. Ewings·Y. Sidis·A. Schneidewind·P. Steffens·A. A. Nugroho·M. Braden
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Abstract

The magnetic excitations in ferromagnetic SrRuO$_3$ were studied by inelastic neutron scattering combining experiments on triple-axis and time-of-flight spectrometers with and without polarization analysis. A quadratic spin-wave dispersion with an anisotropy gap describes the low-energy low-temperature response. The magnon dispersion extends to at least 35 meV and there is no direct evidence for a continuum of Stoner excitations below this energy. However, the magnon response is weakened at higher energy. In addition to the anomalous softening of the spin-wave stiffness and of the gap, which is induced by the topology of the Bloch states, the magnon excitations are broadened in energy and this effect increases upon heating.

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K. Jenni, S. Kunkemöller, A. Tewari, R. A. Ewings, Y. Sidis, A. Schneidewind, P. Steffens, A. A. Nugroho, M. Braden. 2023-05-09. Magnon dispersion in ferromagnetic SrRuO$_3$. https://doi.org/10.1103/physrevb.107.174429

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