%0 Journal Article %1 PhysRevResearch.2.013063 %A Zhang, L.-C. %A Onykiienko, Y. A. %A Buhl, P. M. %A Tymoshenko, Y. V. %A Cermák, P. %A Schneidewind, A. %A Stewart, J. R. %A Henschel, A. %A Schmidt, M. %A Blügel, S. %A Inosov, D. S. %A Mokrousov, Y. %D 2020 %I American Physical Society %J Phys. Rev. Res. %K b %N 1 %P 013063 %R 10.1103/PhysRevResearch.2.013063 %T Magnonic Weyl states in Cu$_2$OSeO$_3$ %U https://link.aps.org/doi/10.1103/PhysRevResearch.2.013063 %V 2 %X The multiferroic ferrimagnet $Cu_2OSeO_3$ 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.

@article{PhysRevResearch.2.013063, abstract = {The multiferroic ferrimagnet $Cu_2OSeO_3$ 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.}, added-at = {2020-01-23T20:21:56.000+0100}, author = {Zhang, L.-C. and Onykiienko, Y. A. and Buhl, P. M. and Tymoshenko, Y. V. and \v{C}erm\'ak, P. and Schneidewind, A. and Stewart, J. R. and Henschel, A. and Schmidt, M. and Bl\"ugel, S. and Inosov, D. S. and Mokrousov, Y.}, biburl = {https://www.bibsonomy.org/bibtex/27f3bd12474941c7bab17875e73716e1d/ctqmat}, day = 21, description = {Phys. Rev. Research 2, 013063 (2020) - Magnonic Weyl states in ${\mathrm{Cu}}_{2}{\mathrm{OSeO}}_{3}$}, doi = {10.1103/PhysRevResearch.2.013063}, interhash = {8beb91e99fbae1a266c554e659e4e704}, intrahash = {7f3bd12474941c7bab17875e73716e1d}, journal = {Phys. Rev. Res.}, keywords = {b}, month = {01}, number = 1, numpages = {9}, pages = 013063, publisher = {American Physical Society}, timestamp = {2023-10-19T14:04:40.000+0200}, title = {Magnonic Weyl states in Cu$_{\mathbf{2}}$OSeO$_{\mathbf{3}}$}, url = {https://link.aps.org/doi/10.1103/PhysRevResearch.2.013063}, volume = 2, year = 2020 }