The magnon band topology due to the Dzyaloshinskii-Moriya interaction (DMI) and its relevant topological thermal Hall effect has been extensively studied in kagome lattice magnets. In this theoretical investigation, we report a new mechanism for phase transitions between topological phases of magnons in kagome ferromagnets by tuning the anisotropic nearest-neighbor ferromagnetic interaction and DMI. Using the linear spin-wave theory, we calculate the Chern number and thermal Hall conductivity of magnons in low temperature regime. We show the magnon band structures and magnonic edge states in each topological phase. From the topological phase diagram, we find a sign reversal of the thermal Hall conductivity upon tuning the modulation factors. We explicitly demonstrate the correspondence of thermal Hall conductivity with the propagation direction of the magnonic edge states. Finally, we discuss candidate materials as experimental realizations of our theoretical model.
|Original language||English (US)|
|Journal||New Journal of Physics|
|State||Published - Feb 3 2022|
Bibliographical noteKAUST Repository Item: Exported on 2022-02-07
Acknowledgements: F.Z. was supported by King Abdullah University of Science and Technology (KAUST). A.M. acknowledges support from the Excellence Initiative of Aix-Marseille Université—A*Midex, a French "Investissements d’Avenir" program. H.L. acknowledge the support from Henan University (No. CJ3050A0240050) and National Natural Science Foundation of China (No. 11804078).
ASJC Scopus subject areas
- Physics and Astronomy(all)