FisMat2017 - Submission - View

Abstract's title: Deterministic and robust room–temperature exchange coupling in monodomain multiferroic BiFeO3 heterostructures
Submitting author: Bruce A. Davidson
Affiliation: Temple University & University of Wisconsin & IOM-CNR/TASC National Laboratory
Affiliation Address: Department of Physics, SERC 443, 1925 N 12th Street, Philadelphia PA USA 19122 & Department of Materials Science and Engineering, University of Wisconsin/Madison, Madison WI 53706 USA & IOM-CNR/TASC National Laboratory, Area Science Park-Basovizza, I-34136 Trieste Italia
Country: United States of America
Oral presentation/Poster (Author's request): Oral presentation
Other authors and affiliations: W. Saenrang1,2, B. A. Davidson1,3,4, F. Maccherozzi5, J. P. Podkaminer1, J. Irwin2, R. D. Johnson6,7, J. W. Freeland8, J. Íñiguez9, J. L. Schad1, K. Reierson2, J. C. Frederick1, C. A. F. Vaz10, L. Howald10, T.H. Kim1, S. Ryu1, M. v. Veenendaal8,11, P.G. Radaelli6, S. S. Dhesi5, M. S. Rzchowski2 and C. B. Eom1,* 1 Department of Materials Science and Engineering, University of Wisconsin, Madison, Wisconsin, 53706, USA 2 Department of Physics, University of Wisconsin, Madison, Wisconsin, 53706, USA 3 CNR-Istituto Officina dei Materiali, TASC National Laboratory, Trieste, I-34149, Italy 4 Department of Physics, Temple University, Philadelphia, Pennsylvania, 19122, USA 5 Diamond Light Source, Harwell Science and Innovation Campus, Didcot, OX11 0DE, UK 6 Department of Physics, University of Oxford, Oxford, OX1 3PU, UK 7 ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QZ, UK 8 Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, 60439, USA 9 Department of Materials Research and Technology, Luxembourg Institute of Science and Technology, Esch/Alzette, L-4362 Luxembourg 10 Swiss Light Source, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland 11 Department of Physics, Northern Illinois University, De Kalb, Illinois, 60115, USA

Exploiting multiferroic BiFeO3 thin films in spintronic devices will require deterministic and robust control of both the internal magnetoelectric coupling in BiFeO3 as well as exchange coupling of its antiferromagnetic order to a ferromagnetic overlayer. Previous reports of exchange coupling in films have utilized approaches based on multistep ferroelectric switching with multiple ferroelectric domains. Because domain walls can be responsible for fatigue, can contain localized charges either intrinsically or via defects, and present technological problems for device reproducibility and scaling, an alternative approach using a monodomain magnetoelectricstate with single–step switching is desirable for practical devices usingBiFeO3. Here we demonstrate a room temperature, deterministic and robust exchange coupling between monodomain BiFeO3 films and a Co overlayer that is “intrinsic” (i.e. not dependent on domain walls). Direct coupling between antiferromagnetic order in BiFeO3 and Co magnetization is observed with ~90° in–plane Co moment rotation upon single-step switching that is reproducible for hundreds of cycles. This has important consequences for practical, low power non-volatile magnetoelectric devices utilizing BiFeO3.