Charge-Transfer-Induced Interfacial Ferromagnetism in Ferromagnet-Free Oxide Heterostructures

作     者：Zheng, Jie Shi, Wenxiao Li, Zhe Zhang, Jing Yang, Chao-Yao Zhu, Zhaozhao Wang, Mengqin Zhang, Jine Han, Furong Zhang, Hui Chen, Yunzhong Hu, Fengxia Shen, Baogen Chen, Yuansha Sun, Jirong 

作者机构：Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences Beijing100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing100049 China Songshan Lake Materials Laboratory Guangdong Dongguan523808 China Department of Materials Science and Engineering National Yang Ming Chiao Tung University Hsinchu300 Taiwan School of Integrated Circuit Science and Engineering Beihang University Beijing100191 China Ningbo Institute of Materials Technology & Engineering Chinese Academy of Sciences Zhejiang Ningbo315201 China Spintronics Institute School of Physics and Technology University of Jinan Jinan250022 China 

出 版 物：《ACS Nano》 (ACS Nano)

年 卷 期：2024年第18卷第12期

页      面：9232-9241页

核心收录：

学科分类：0808[工学-电气工程] 070207[理学-光学] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 0817[工学-化学工程与技术] 0806[工学-冶金工程] 070203[理学-原子与分子物理] 0703[理学-化学] 0702[理学-物理学] 0801[工学-力学（可授工学、理学学位）] 

基　　金：This work has been supported by the National Key R&D Program of China (2023YFA1607400  2022YFA1403302  and 2019YFA0704904)  the Science Center of the National Science Foundation of China (52088101)  the National Natural Science Foundation of China (11934016  12274443  T2394472  and 12304149) and the Key Program of the Chinese Academy of Sciences (XDB33030200). Jirong Sun acknowledges the support of the Project for Innovative Research Team of National Natural Science Foundation of China (11921004). Jing Zhang acknowledges the support of the Guangdong Basic and Applied Basic Research Foundation (2022A1515110648 and 2023A1515010953). We acknowledge Beamline BL08U1A and BL02U2 at the Shanghai Synchrotron Radiation Facility (SSRF) for the XAS characterizations and the Synergetic Extreme Condition User Facility (SECUF) for the Hall effect characterizations 

主　　题：Ferromagnetism 

摘      要：Due to the strong interlayer coupling between multiple degrees of freedom, oxide heterostructures have demonstrated exotic properties that are not shown by their bulk counterparts. One of the most interesting properties is ferromagnetism at the interface formed between nonferromagnetic compounds. Here we report on the interfacial ferromagnetic phase induced in the superlattices consisting of the two paramagnetic oxides CaRuO3 (CRO) and LaNiO3 (LNO). By varying the sublayer thickness in the superlattice period, we demonstrate that the ferromagnetic order has been established in both CaRuO3 and LaNiO3 sublayers, exhibiting an identical Curie temperature of ∼75 K. The X-ray absorption spectra suggest a strong charge transfer from Ru to Ni at the interface, triggering superexchange interactions between Ru/Ni ions and giving rise to the emergent ferromagnetic phase. Moreover, the X-ray linear dichroism spectra reveal the preferential occupancy of the d3z2-r2 orbital for the Ru ions and the dx2-y2 orbital for the Ni ions in the heterostructure. This leads to different magnetic anisotropy of the superlattices when they are dominated by CRO or LNO sublayers. This work clearly demonstrates a charge-transfer-induced interfacial ferromagnetic phase in the whole ferromagnet-free oxide heterostructures, offering a feasible way to tailor oxide materials for desired functionalities. © 2024 American Chemical Society.