Thickness dependent manipulation of uniaxial magnetic anisotropy in Fe-thin films by oblique deposition  

作　　者：Qeemat Gul Wei He Yan Li Rui Sun Na Li Xu Yang Yang Li Zi-Zhao Gong ZongKai Xie Xiang-Qun Zhang Zhao-Hua Cheng Qeemat Gul;何为;李岩;孙瑞;李娜;杨旭;李阳;弓子召;谢宗凯;张向群;成昭华(State Key Laboratory of Magnetism and Beijing National Laboratory for Condensed Matter Physics, Institute of Physics,Chinese Academy of Sciences;School of Physical Sciences, University of Chinese Academy of Sciences)

机构地区：[1]State Key Laboratory of Magnetism and Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China [2]School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Chinese Physics B》2018年第9期577-584,共8页中国物理B（英文版）

基　　金：Project supported by the National Basic Research Program of China(Grant Nos.2015CB921403 and 2016YFA0300701);the National Natural Science Foundation of China(Grant Nos.51427801,11374350,and 51671212);the Chinese Government Scholarship(Grant No.2015GXYG37)

摘　　要：The uniaxial magnetic anisotropy of obliquely deposited Fe（001）/Pd film on MgO（001） substrate is investigated as a function of deposition angle and film thickness. The values of incidence angle of Fe flux relative to surface normal of the substrate are 0°, 45°, 55°, and 70°, respectively. In-situ low energy electron diffraction is employed to investigate the surface structures of the samples. The Fe film thicknesses are determined to be 50 ML, 45 ML, 32 ML, and 24 ML（1 ML = 0.14 nm） by performing x-ray reflectivity on the grown samples, respectively. The normalized remanent magnetic saturation ratio and coercivity are obtained by the longitudinal surface magneto-optical Kerr effect. Here, the magnetic anisotropy constants are quantitatively determined by fitting the anisotropic magnetoresistance curves under different fields.These measurements show four-fold cubic anisotropy in a large Fe film thickness（50 ML） sample, but highly in-plane uniaxial magnetic anisotropies in thin films（24 ML and 32 ML） samples. In the obliquely deposited Fe films, the coercive fields and the uniaxial magnetic anisotropies（UMAs） increase as the deposition angle becomes more and more tilted. In addition, the UMA decreases with the increase of the Fe film thickness. Our work provides the possibility of manipulating uniaxial magnetic anisotropy, and paves the way to inducing UMA by oblique deposition with smaller film thickness.The uniaxial magnetic anisotropy of obliquely deposited Fe（001）/Pd film on MgO（001） substrate is investigated as a function of deposition angle and film thickness. The values of incidence angle of Fe flux relative to surface normal of the substrate are 0°, 45°, 55°, and 70°, respectively. In-situ low energy electron diffraction is employed to investigate the surface structures of the samples. The Fe film thicknesses are determined to be 50 ML, 45 ML, 32 ML, and 24 ML（1 ML = 0.14 nm） by performing x-ray reflectivity on the grown samples, respectively. The normalized remanent magnetic saturation ratio and coercivity are obtained by the longitudinal surface magneto-optical Kerr effect. Here, the magnetic anisotropy constants are quantitatively determined by fitting the anisotropic magnetoresistance curves under different fields.These measurements show four-fold cubic anisotropy in a large Fe film thickness（50 ML） sample, but highly in-plane uniaxial magnetic anisotropies in thin films（24 ML and 32 ML） samples. In the obliquely deposited Fe films, the coercive fields and the uniaxial magnetic anisotropies（UMAs） increase as the deposition angle becomes more and more tilted. In addition, the UMA decreases with the increase of the Fe film thickness. Our work provides the possibility of manipulating uniaxial magnetic anisotropy, and paves the way to inducing UMA by oblique deposition with smaller film thickness.

关 键 词：iron thin films oblique deposition magnetic anisotropy MAGNETORESISTANCE 

分 类 号：O484[理学—固体物理]