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arXiv · 2103.03885

Universal spin wave damping in magnetic Weyl semimetals

Predrag Nikolić
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Abstract

We analyze the decay of spin waves into Stoner excitations in magnetic Weyl semimetals. The lifetime of a mode is found to have a universal dependence on its frequency and momentum, and on a few parameters that characterize the relativistic Weyl spectrum. At the same time, Gilbert damping by Weyl electrons is absent. The decay rate of spin waves is calculated perturbatively using the s-d model of itinerant Weyl or Dirac electrons coupled to local moments. We show that many details of the Weyl spectrum, such as the momentum-space locations, dispersions and sizes of the Weyl Fermi pockets, can be deduced indirectly by probing the spin waves of local moments using inelastic neutron scattering.

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Predrag Nikolić. 2021-03-05. Universal spin wave damping in magnetic Weyl semimetals. https://doi.org/10.1103/physrevb.104.024414

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