@article{bed3f2e5f58a4ea686d4eefff893dd57,
title = "Magnetic anisotropy in ferromagnetic CrI3",
abstract = "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.",
author = "Lebing Chen and Chung, {Jae Ho} and Tong Chen and Chunruo Duan and Astrid Schneidewind and Igor Radelytskyi and Voneshen, {David J.} and Ewings, {Russell A.} and Stone, {Matthew B.} and Kolesnikov, {Alexander I.} and Barry Winn and Songxue Chi and Mole, {R. A.} and Yu, {D. H.} and Bin Gao and Pengcheng Dai",
note = "Funding Information: We are grateful to R. J. Birgeneau and Andriy Nevidomskyy for helpful discussions. The INS and single crystal synthesis work at Rice was supported by the US NSF Grant No. DMR-1700081 and the Robert A. Welch Foundation Grant No. C-1839 (P.D.), respectively. The work of J.-H.C. was supported by the National Research Foundation of Korea (Grants No. NRF-2016R1D1A1B03934157 and No. NRF2017K1A3A7A09016303). A portion of this research used resources at the Spallation Neutron Source and the High Flux Isotope Reactor, a DOE Office of Science User Facility operated by ORNL. Experiments at the ISIS Neutron and Muon Source were supported by a beam time allocation RB1820251 from the Science and Technology Facilities Council . Publisher Copyright: {\textcopyright} 2020 American Physical Society.",
year = "2020",
month = apr,
day = "1",
doi = "10.1103/PhysRevB.101.134418",
language = "English",
volume = "101",
journal = "Physical Review B-Condensed Matter",
issn = "1098-0121",
publisher = "American Institute of Physics Publising LLC",
number = "13",
}