Abstract
Hexagonal HoMnO3, a two-dimensional Heisenberg antiferromagnet, has been studied via inelastic neutron scattering. A simple Heisenberg model with a single-ion anisotropy describes most features of the spin-wave dispersion curves. However, there is shown to be a renormalization of the magnon energies located at around 11 meV. Since both the magnon-magnon interaction and magnon-phonon coupling can affect the renormalization in a noncollinear magnet, we have accounted for both of these couplings by using a Heisenberg XXZ model with 1/S expansions [1] and the Einstein site phonon model [13], respectively. This quantitative analysis leads to the conclusion that the renormalization effect primarily originates from the magnon-phonon coupling, while the spontaneous magnon decay due to the magnon-magnon interaction is suppressed by strong two-ion anisotropy.
| Original language | English |
|---|---|
| Article number | 201113 |
| Journal | Physical Review B |
| Volume | 97 |
| Issue number | 20 |
| DOIs | |
| State | Published - May 25 2018 |
| Externally published | Yes |
Funding
Acknowledgments. We thank C. Broholm and M. Kenzelmann for useful discussions. The inelastic neutron scattering experiment at the Japan Proton Accelerator Research Complex (J-PARC) was performed under the user program (Proposal No. 2014B0154). Work at the Institute for Basic Science (IBS) Center for Correlated Electron Systems (CCES) was supported by the research program of the Institute for Basic Science (IBS-R009-G1).