Magnonic Weyl states in Cu2OSeO3

Zhang LC, Onykiienko YA, Buhl PM, Tymoshenko Y, Cermak P, Schneidewind A, Stewart JR, Henschel A, Schmidt M, Bluegel S, Inosov DS, Mokrousov Y (2020)

Publication Type: Journal article

Publication year: 2020

Journal

Physical Review Research American Physical Society

Book Volume: 2

Article Number: 013063

Journal Issue: 1

DOI: 10.1103/PhysRevResearch.2.013063

Abstract

The multiferroic ferrimagnet Cu2OSeO3 with a chiral crystal structure has attracted a lot of recent attention due to the emergence of a magnetic skyrmion order in this material. Here, the topological properties of its magnon excitations are systematically investigated by linear spin-wave theory and inelastic neutron scattering. When considering Heisenberg exchange interactions only, two degenerate Weyl magnon nodes with topological charges ±2 are observed at high-symmetry points. Each Weyl point splits into two as the symmetry of the system is further reduced by including into consideration the nearest-neighbor Dzyaloshinskii-Moriya interaction, crucial for obtaining an accurate fit to the experimental spin-wave spectrum. Also, one additional pair of Weyl points appears near the R point. The predicted topological properties are verified by surface state and Chern number analysis. Additionally, we predict that a measurable thermal Hall conductivity can be associated with the emergence of the Weyl points, the position and number of which can be tuned by modifying the Dzyaloshinskii-Moriya interaction in the system.

Involved external institutions

Forschungszentrum Jülich / Research Centre Jülich (FZJ) DE Germany (DE) Technische Universität Dresden DE Germany (DE) Johannes Gutenberg-Universität Mainz (JGU) DE Germany (DE) Rutherford Appleton Laboratory GB United Kingdom (GB) Max-Planck-Institut für Chemische Physik fester Stoffe (MPI CPfS) / Max Planck Institute for Chemical Physics of Solids DE Germany (DE)

How to cite

APA:

Zhang, L.-C., Onykiienko, Y.A., Buhl, P.M., Tymoshenko, Y., Cermak, P., Schneidewind, A.,... Mokrousov, Y. (2020). Magnonic Weyl states in Cu2OSeO3. Physical Review Research, 2(1). https://doi.org/10.1103/PhysRevResearch.2.013063

MLA:

Zhang, L-C, et al. "Magnonic Weyl states in Cu2OSeO3." Physical Review Research 2.1 (2020).

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