Atomic origin of magnetic coupling of antiphase boundaries in magnetite thin films  

作　　者：Chunyang Gao Yixiao Jiang Tingting Yao Ang Tao Xuexi Yan Xiang Li Chunlin Chen Xiu-Liang Ma Hengqiang Ye 

机构地区：[1]Shenyang National Laboratory for Materials Science,Institute of Metal Research,Chinese Academy of Sciences,School of Materials Science and Engineering,University of Science and Technology of China,Shenyang 110016,China [2]Ji Hua Laboratory,Foshan 528200,China

出　　处：《Journal of Materials Science & Technology》2022年第12期92-99,共8页材料科学技术（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.51771200,51971224,51801215);LiaoNing Revitalization Talents Program(No.XLYC1802088);the Key Research Program of Frontier Sciences,CAS(No.QYZDY-SSW-JSC027);Ji Hua Laboratory Project X210141TL210 for cooperation。

摘　　要：Revealing the magnetic coupling nature of boundary defects is crucial for in-depth understanding of the behavior and properties of magnetic materials and devices.Here,magnetite(i.e.,Fe_(3)O_(4))thin films were grown epitaxially on(100)SrTiOsingle-crystal substrates by pulsed laser deposition.Atomic-scale scanning transmission electron microscopy characterizations reveal that three types of antiphase boundaries(APBs)are formed in the Fe_(3)O_(4)thin film.They are the(100)APB that is formed on the(100)plane with a crystal translation of(1/4)a[011^(-)],the typeⅠand typeⅡ(110)APBs that are both formed on the(110)plane with the same crystal translation of(1/4)a[101]but different terminated atomic planes.The typeⅠ(110)APB is terminated at the atomic plane with mixed tetrahedral-and octahedral-sites Fe atoms,the typeⅡ(110)APB is terminated at the octahedral-site Fe plane.First-principles calculations reveal that the(100)APB and the typeⅠ(110)APB tend to form the ferromagnetic coupling that will not decrease the spin polarization of Fe_(3)O_(4)films,while the typeⅡ(110)APB prefers to form the antiferromagnetic coupling that will degrade the magnetic properties.The magnetic coupling modes of the APBs are closely related to the Fe-O-Fe bond angles across the boundaries.

关 键 词：Fe_(3)O_(4) Transmission electron microscopy Antiphase boundary Magnetic coupling First-principles calculations 

分 类 号：TB383.2[一般工业技术—材料科学与工程]