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arXiv · 1609.01973

Emerging magnetism and anomalous Hall effect in iridate-manganite heterostructures

Abstract

Strong Coulomb repulsion and spin-orbit coupling are known to give rise to exotic physical phenomena in transition metal oxides. Initial attempts to investigate systems where both of these fundamental interactions are comparably strong, such as 3d and 5d complex oxide superlattices, have revealed properties that only slightly differ from the bulk ones of the constituent materials. Here, we observe that the interfacial coupling between the 3d antiferromagnetic insulator SrMnO3 and the 5d paramagnetic metal SrIrO3 is enormously strong, yielding an anomalous Hall response as the result of charge transfer driven interfacial ferromagnetism. These findings show that low dimensional spin-orbit entangled 3d-5d interfaces provide an avenue to uncover technologically relevant physical phenomena unattainable in bulk materials.

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John Nichols, Xiang Gao, Shinbuhm Lee, Tricia L. Meyer, John W. Freeland, Valeria Lauter, Di Yi, Jian Liu, Daniel Haskel, Jonathan R. Petrie, Er-Jia Guo, Andreas Herklotz, Dongkyu Lee, Thomas Z. Ward, Gyula Eres, Michael R. Fitzsimmons, Ho Nyung Lee. 2016-09-07. Emerging magnetism and anomalous Hall effect in iridate-manganite heterostructures. https://doi.org/10.1038/ncomms12721

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