Abstract
Using THz spectroscopy, we show that the spin-wave spectrum of multiferroic BiFeO3 in its high-field canted antiferromagnetic state is well described by a spin model that violates rhombohedral symmetry. We demonstrate that the monoclinic distortion of the canted antiferromagnetic state is induced by the single-ion magnetoelastic coupling between the lattice and the two nearly antiparallel spins. The revised spin model for BiFeO3 contains two new single-ion anisotropy terms that violate rhombohedral symmetry and depend on the direction of the magnetic field.
| Original language | English |
|---|---|
| Article number | 214410 |
| Journal | Physical Review B |
| Volume | 102 |
| Issue number | 21 |
| DOIs | |
| State | Published - Dec 9 2020 |
Funding
We thank Bianca Trociewitz for her contribution to the design of probes and for technical assistance in Tallahassee. Research was supported by the European Regional Development Fund Project No. TK134 and by the Estonian Ministry of Education and Research Council Grants No. IUT23-03 and No. PRG736, by the bilateral program of the Estonian and Hungarian Academies of Sciences under Contract No. SNK-64/2013, by the Hungarian NKFIH Grants No. K 124176 and No. ANN 122879, by the BME-Nanonotechnology and Materials Science FIKP grant of EMMI (BME FIKP-NAT), by the FWF Austrian Science Fund I 2816-N27, and by the Deutsche Forschungsgemeinschaft (DFG) via the Transregional Research Collaboration TRR 80: From Electronic Correlations to Functionality (Augsburg-Munich-Stuttgart). T.D. acknowledges funding support from Augusta University and SYSU Grant No. OEMT-2017-KF-06 and R.S.F. by the U.S. Department of Energy, Office of Basic Energy Sciences, Materials Sciences and Engineering Division. A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by NSF Cooperative Agreement No. DMR-1644779 and the State of Florida. The support of the HFML-RU/FOM, member of the European Magnetic Field Laboratory (EMFL), is acknowledged. This paper has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this paper, or allow others to do so, for U.S. Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan .