Abstract
CrSBr is an air-stable two-dimensional (2D) van der Waals semiconducting magnet with great technological promise, but its atomic-scale magnetic interactions—crucial information for high-frequency switching—are poorly understood. An experimental study is presented to determine the CrSBr magnetic exchange Hamiltonian and bulk magnon spectrum. The A-type antiferromagnetic order using single crystal neutron diffraction is confirmed here. The magnon dispersions are also measured using inelastic neutron scattering and rigorously fit the excitation modes to a spin wave model. The magnon spectrum is well described by an intra-plane ferromagnetic Heisenberg exchange model with seven nearest in-plane exchanges. This fitted exchange Hamiltonian enables theoretical predictions of CrSBr behavior: as one example, the fitted Hamiltonian is used to predict the presence of chiral magnon edge modes with a spin-orbit enhanced CrSBr heterostructure.
| Original language | English |
|---|---|
| Article number | 2202467 |
| Journal | Advanced Science |
| Volume | 9 |
| Issue number | 25 |
| DOIs | |
| State | Published - Sep 5 2022 |
Funding
A.S. acknowledges helpful discussions with Peter Holdsworth and Paul McClarty. This research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. The PPMS used to perform vibrating sample magnetometry measurements was purchased with financial support from the NSF through a supplement to award DMR‐1751949. Synthesis was supported by the National Science Foundation (NSF) Materials Research Science and Engineering Centers (MRSEC) program (DMR‐2011738) and as a part of Programmable Quantum Materials, an Energy Frontier Research Center funded by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), under award DE‐SC0019443. A.S. acknowledges helpful discussions with Peter Holdsworth and Paul McClarty. This research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. The PPMS used to perform vibrating sample magnetometry measurements was purchased with financial support from the NSF through a supplement to award DMR-1751949. Synthesis was supported by the National Science Foundation (NSF) Materials Research Science and Engineering Centers (MRSEC) program (DMR-2011738) and as a part of Programmable Quantum Materials, an Energy Frontier Research Center funded by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), under award DE-SC0019443.
| Funders | Funder number |
|---|---|
| National Science Foundation | |
| U.S. Department of Energy | |
| Office of Science | |
| Basic Energy Sciences | DE‐SC0019443 |
| Oak Ridge National Laboratory | DMR‐1751949 |
| Materials Research Science and Engineering Center, Harvard University | DMR‐2011738 |
Keywords
- 2D materials
- magnetism
- neutron scattering
- spin waves