We use neutron scattering to show that ferromagnetic (FM) phase transition in the two-dimensional (2D) honeycomb lattice CrI3 is a weakly first order transition and controlled by spin-orbit coupling (SOC) induced magnetic anisotropy, instead of magnetic exchange coupling as in a conventional ferromagnet. With increasing temperature, the magnitude of magnetic anisotropy, seen as a spin gap at the Brillouin zone center, decreases in a power law fashion and vanishes at TC, while the in-plane and c-axis spin-wave stiffnesses associated with magnetic exchange couplings remain robust at TC. We also compare parameter regimes where spin waves in CrI3 can be described by a Heisenberg Hamiltonian with Dzyaloshinskii-Moriya interaction or a Heisenberg-Kitaev Hamiltonian. These results suggest that the SOC induced magnetic anisotropy plays a dominant role in stabilizing the FM order in single layer 2D van der Waals ferromagnets.
Chen, Lebing, Chung, Jae-Ho, Chen, Tong, Duan, Chunruo, Schneidewind, Astrid, Radelytskyi, Igor, Voneshen, David J., Ewings, Russell A., Stone, Matthew B., Kolesnikov, Alexander I., Winn, Barry L., Chi, Songxue, Mole, R. A., Yu, D. H., Gao, Bin, & Dai, Pengcheng (2020). Magnetic anisotropy in ferromagnetic <math><msub><mi>CrI</mi><mn>3</mn></msub></math>. Physical Review. B, 101(13). https://doi.org/10.1103/PhysRevB.101.134418
@article{osti_1615985,
author = {Chen, Lebing and Chung, Jae-Ho and Chen, Tong and Duan, Chunruo and Schneidewind, Astrid and Radelytskyi, Igor and Voneshen, David J. and Ewings, Russell A. and Stone, Matthew B. and Kolesnikov, Alexander I. and others},
title = {Magnetic anisotropy in ferromagnetic <math><msub><mi>CrI</mi><mn>3</mn></msub></math>},
annote = {We use neutron scattering to show that ferromagnetic (FM) phase transition in the two-dimensional (2D) honeycomb lattice CrI3 is a weakly first order transition and controlled by spin-orbit coupling (SOC) induced magnetic anisotropy, instead of magnetic exchange coupling as in a conventional ferromagnet. With increasing temperature, the magnitude of magnetic anisotropy, seen as a spin gap at the Brillouin zone center, decreases in a power law fashion and vanishes at TC, while the in-plane and c-axis spin-wave stiffnesses associated with magnetic exchange couplings remain robust at TC. We also compare parameter regimes where spin waves in CrI3 can be described by a Heisenberg Hamiltonian with Dzyaloshinskii-Moriya interaction or a Heisenberg-Kitaev Hamiltonian. These results suggest that the SOC induced magnetic anisotropy plays a dominant role in stabilizing the FM order in single layer 2D van der Waals ferromagnets.},
doi = {10.1103/PhysRevB.101.134418},
url = {https://www.osti.gov/biblio/1615985},
journal = {Physical Review. B},
issn = {ISSN PRBMDO},
number = {13},
volume = {101},
place = {United States},
publisher = {American Physical Society (APS)},
year = {2020},
month = {04}}
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
National Research Foundation of Korea; National Science Foundation (NSF); Robert A. Welch Foundation; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 637, Issue 1https://doi.org/10.1016/j.nima.2011.01.173
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 834https://doi.org/10.1016/j.nima.2016.07.036