气候变化领域集成服务门户(CCPortal): Atomic-scale determination of spontaneous magnetic reversal in oxide heterostructures

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DOI	10.1073/pnas.1819570116
	Atomic-scale determination of spontaneous magnetic reversal in oxide heterostructures
	Saghayezhian M.; Kouser S.; Wang Z.; Guo H.; Jin R.; Zhang J.; Zhu Y.; Pantelides S.T.; Plummer E.W.
发表日期	2019
ISSN	0027-8424
起始页码	10309
结束页码	10316
卷号	116 期号:21
英文摘要	Interfaces between transition metal oxides are known to exhibit emerging electronic and magnetic properties. Here we report intriguing magnetic phenomena for La2/3Sr1/3MnO3 films on an SrTiO3 (001) substrate (LSMO/STO), where the interface governs the macroscopic properties of the entire monolithic thin film. The interface is characterized on the atomic level utilizing scanning transmission electron microscopy and electron energy loss spectroscopy (STEMEELS), and density functional theory (DFT) is employed to elucidate the physics. STEM-EELS reveals mixed interfacial stoichiometry, subtle lattice distortions, and oxidation-state changes. Magnetic measurements combined with DFT calculations demonstrate that a unique form of antiferromagnetic exchange coupling appears at the interface, generating a novel exchange spring-type interaction that results in a remarkable spontaneous magnetic reversal of the entire ferromagnetic film, and an inverted magnetic hysteresis, persisting above room temperature. Formal oxidation states derived from electron spectroscopy data expose the fact that interfacial oxidation states are not consistent with nominal charge counting. The present work demonstrates the necessity of atomically resolved electron microscopy and spectroscopy for interface studies. Theory demonstrates that interfacial nonstoichiometry is an essential ingredient, responsible for the observed physical properties. The DFT-calculated electrostatic potential is flat in both the LSMO and STO sides (no internal electric field) for both Sr-rich and stoichiometric interfaces, while the DFT-calculated charge density reveals no charge transfer/ accumulation at the interface, indicating that oxidation-state changes do not necessarily reflect charge transfer and that the concept of polar mismatch is not applicable in metal-insulator polar-nonpolar interfaces. © 2019 National Academy of Sciences. All rights reserved.
英文关键词	Density functional theory; Electron microscopy; Magnetism; Oxide interfaces; Thin films
语种	英语
scopus关键词	ferromagnetic material; lanthanum; manganese oxide; oxide; strontium; titanium dioxide; Article; chemical interaction; chemical structure; density functional theory; electron energy loss spectroscopy; magnetism; oxidation; physics; priority journal; room temperature; scanning transmission electron microscopy; static electricity; stoichiometry
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160392
作者单位	Saghayezhian, M., Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, United States; Kouser, S., Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235, United States, Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, TN 37235, United States, Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, United States; Wang, Z., Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, United States, Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973, United States; Guo, H., Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, United States; Jin, R., Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, United States; Zhang, J., Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70...
推荐引用方式 GB/T 7714	Saghayezhian M.,Kouser S.,Wang Z.,et al. Atomic-scale determination of spontaneous magnetic reversal in oxide heterostructures[J],2019,116(21).
APA	Saghayezhian M..,Kouser S..,Wang Z..,Guo H..,Jin R..,...&Plummer E.W..(2019).Atomic-scale determination of spontaneous magnetic reversal in oxide heterostructures.Proceedings of the National Academy of Sciences of the United States of America,116(21).
MLA	Saghayezhian M.,et al."Atomic-scale determination of spontaneous magnetic reversal in oxide heterostructures".Proceedings of the National Academy of Sciences of the United States of America 116.21(2019).