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Multiferroics: progress and prospects in thin films

Abstract

Multiferroic materials, which show simultaneous ferroelectric and magnetic ordering, exhibit unusual physical properties — and in turn promise new device applications — as a result of the coupling between their dual order parameters. We review recent progress in the growth, characterization and understanding of thin-film multiferroics. The availability of high-quality thin-film multiferroics makes it easier to tailor their properties through epitaxial strain, atomic-level engineering of chemistry and interfacial coupling, and is a prerequisite for their incorporation into practical devices. We discuss novel device paradigms based on magnetoelectric coupling, and outline the key scientific challenges in the field.

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Figure 1: Publications per year with 'magnetoelectric' as a keyword.
Figure 2: Schematics of the three types of model thin-film architectures reviewed here.
Figure 3: A schematic illustration of a thin-film deposition system (in this case a laser MBE system) that is attached to a synchrotron beamline.
Figure 4: Thin-film multiferroic nanostructures.
Figure 5: Essence of an electrically tuneable magnetic device.

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Acknowledgements

Clearly, this work represents the cumulative efforts of many researchers around the world. Specifically, we acknowledge several key collaborators (in alphabetical order): L. Q. Chen (Pennsylvania State Univ. (PSU)), L. E. Cross (PSU), C. Ederer (Columbia Univ. ), C. B. Eom (Univ. Wisconsin), M. Fiebig (Univ. Bonn), V. Gopalan (PSU), J. Kreisel (Univ. Grenoble), S. Ogale (Univ. Maryland), K. M. Rabe (Rutgers Univ.), D. Schlom (PSU), H. Schmid (Univ. Geneva), A. Scholl (ALS-LBL), J. F. Scott (Univ. Cambridge), D. Viehland (Virginia Tech.), M. Wuttig (Univ. Maryland), F. Zavaliche (Seagate Technologies) and T. Zhao (Seagate Technologies). We also thank past and present members of our research groups at Berkeley and Santa Barbara. We thank the following funding agencies: ONR, DOE and NSF (R.R.) and NSF (N.A.S.).

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Ramesh, R., Spaldin, N. Multiferroics: progress and prospects in thin films. Nature Mater 6, 21–29 (2007). https://doi.org/10.1038/nmat1805

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