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Emergent phenomena at oxide interfaces

From magnetism, ferroelectricity and superconductivity to electrical and thermal properties, oxides show a broad range of phenomena of fundamental as well as practical relevance. Reviewed here are the emergent phenomena arising at the interface between oxide materials, which have attracted considerable interest based on advances in thin-film deposition techniques.

Abstract

Recent technical advances in the atomic-scale synthesis of oxide heterostructures have provided a fertile new ground for creating novel states at their interfaces. Different symmetry constraints can be used to design structures exhibiting phenomena not found in the bulk constituents. A characteristic feature is the reconstruction of the charge, spin and orbital states at interfaces on the nanometre scale. Examples such as interface superconductivity, magneto-electric coupling, and the quantum Hall effect in oxide heterostructures are representative of the scientific and technological opportunities in this rapidly emerging field.

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Figure 1
Figure 2: Orbital and spin configurations at interfaces.
Figure 3: Atomic and charge structure of pervoskite heterointerfaces.
Figure 4: Modulation doping of holes using polar surfaces.
Figure 5: Heterostructure of metallic LaNiO3 with partially occupied Ni eg orbitals (LNO, blue) and insulating LaAlO3 (LAO, white)46.
Figure 6: Magnetization induced second-harmonic generation (MSHG) for a tricolour superlattice composed of LaMnO3 (LMO), SrMnO3 (SMO), and LaAlO3 (LAO).
Figure 7: Various device structures used to produce 2D or interface superconductivity.
Figure 8: Fractional quantum Hall effect in ZnO.

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Acknowledgements

This work was partly supported by the Japan Society for the Promotion of Science (JSPS) through its Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST Program). H.Y.H. acknowledges support from the Department of Energy, Office of Basic Energy Sciences, under contract DE-AC02-76SF00515. B.K. acknowledges support by the German Science Foundation under collaborative Grant No. SFB/TRR80. N.N. acknowledges support by MEXT Grand-in-Aid No. 20740167, 19048008, 19048015, 21244053, and the Strategic International Cooperative Program (Joint Research Type) from the Japan Science and Technology Agency.

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Hwang, H., Iwasa, Y., Kawasaki, M. et al. Emergent phenomena at oxide interfaces. Nature Mater 11, 103–113 (2012). https://doi.org/10.1038/nmat3223

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