Abstract
The antiferromagnetic (AFM) compound MnBi2Te4 is suggested to be the first realization of an AFM topological insulator. We report on inelastic neutron scattering studies of the magnetic interactions in MnBi2Te4 that possess ferromagnetic triangular layers with AFM interlayer coupling. The spin waves display a large spin gap and pairwise exchange interactions within the triangular layer are long ranged and frustrated by large next-nearest neighbor AFM exchange. The degree of frustration suggests proximity to a variety of magnetic phases, potentially including skyrmion phases, which could be accessed in chemically tuned compounds or upon the application of symmetry-breaking fields.
| Original language | English |
|---|---|
| Article number | 167204 |
| Journal | Physical Review Letters |
| Volume | 124 |
| Issue number | 16 |
| DOIs | |
| State | Published - Apr 24 2020 |
Funding
We would like to thank Q. Zhang and M. McGuire for magnetic powder diffraction measurements. Work at Oak Ridge National Laboratory (ORNL) and Ames Laboratory was supported by the U.S. Department of Energy (U.S. DOE), Office of Basic Energy Sciences, Division of Materials Sciences and Engineering. A portion of this research used resources at the Spallation Neutron Source, a U.S. DOE Office of Science User Facility operated by ORNL. Ames Laboratory is operated for the U.S. DOE by Iowa State University under Contract No. DE-AC02-07CH11358. E. G. and L. K. acknowledge the support from the U.S. DOE Early Career Research Program. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility operated under Contract No. DE-AC02-05CH11231.
| Funders | Funder number |
|---|---|
| U.S. Department of Energy | DE-AC02-05CH11231 |
| Basic Energy Sciences | |
| Oak Ridge National Laboratory | |
| Iowa State University | DE-AC02-07CH11358 |
| Division of Materials Sciences and Engineering |