Anisotropic magnetic couplings and structure-driven canted to collinear transitions in Sr2IrO4 by magnetically constrained noncollinear DFT
- Author(s)
- Peitao Liu, Sergii Khmelevskyi, Bongjae Kim, Martijn Marsman, Dianzhong Li, Xing-Qiu Chen, D. D. Sarma, Georg Kresse, Cesare Franchini
- Abstract
We study the canted magnetic state in Sr2IrO4 using fully relativistic density functional theory (DFT) including an on-site Hubbard U correction. A complete magnetic phase diagram with respect to the tetragonal distortion and the rotation of IrO6 octahedra is constructed, revealing the presence of two types of canted to collinear magnetic transitions: a spin-flop transition with increasing tetragonal distortion and a complete quenching of the basal weak ferromagnetic moment below a critical octahedral rotation. Moreover, we put forward a scheme to study the anisotropic magnetic couplings by mapping magnetically constrained noncollinear DFT onto a general spin Hamiltonian. This procedure allows for the simultaneous account and direct control of the lattice, spin, and orbital interactions within a fully ab initio scheme. We compute the isotropic, single site anisotropy and Dzyaloshinskii-Moriya (DM) coupling parameters, and clarify that the origin of the canted magnetic state in Sr2IrO4 arises from the structural distortions and the competition between isotropic exchange and DM interactions.
- Organisation(s)
- Computational Materials Physics
- External organisation(s)
- Chinese Academy of Sciences (CAS), Indian Institute of Science, Budapest University of Technology and Economics
- Journal
- Physical Review B
- Volume
- 92
- No. of pages
- 6
- ISSN
- 1098-0121
- DOI
- https://doi.org/10.1103/PhysRevB.92.054428
- Publication date
- 08-2015
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103025 Quantum mechanics, 103036 Theoretical physics, 103015 Condensed matter, 103009 Solid state physics
- ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials, Condensed Matter Physics
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/9b1ad3ae-b5de-49d0-835b-58cb80d8199a