摘要
Control of magnetic anisotropy in low-dimensional systems is of paramount importance in terms of their fundamental and technological perspectives.La_(0.7)Sr_(0.3)MnO_(3)(LSMO)is a ferromagnetic half-metal with a high Curie temperature and many efforts have been made to control its magnetic anisotropy.However,the relationship between the evolution of the magnetic anisotropy orientation and the electronic structure of low-dimensional LSMO still remains poorly understood.Here,the high-quality superlattices comprised of LSMO and SrMnO_(3)(SMO)layers are synthesized with a compatible structure at the atomic scale.Their magnetic anisotropy is gradually varied from planar to perpendicular by increasing the SMO thickness,and the special fourfold magnetic anisotropy is also observed at the intermediate superlattice thickness.The evolution of the magnetic anisotropy in these systems is confirmed by the electronic transport and magnetic measurements.Moreover,X-ray linear dichroism measurements and first-principles calculations reveal the interfacial orbital reconstruction with the in-plane to out-ofplane magnetic reorientation transition.Therefore,a new microscopic method for magnetic anisotropy manipulation is developed in the present study,enabling discovery of novel phenomena as well as control of the magnetic properties.
低维系统磁各向异性的调控无论对于基础研究领域还是对于器件的工业化应用都有着重要的意义.La_(0.7)Sr_(0.3)MnO_(3)(LSMO)展现出的高居里温度以及铁磁半金属特性,吸引了大量的科研人员对其磁各向异性进行研究,但直到目前为止,关于低维LSMO薄膜中磁各向异性与其电子结构之间的关系尚不明确.本文中,我们利用脉冲激光沉积系统制备了高质量、原子级平整的LSMO/SrMnO_(3)(SMO)超晶格.磁性及电输运实验结果表明,随着SMO厚度的增加,超晶格的磁性易轴由面内转向面外方向,并且在一定厚度时,超晶格的磁各向异性显示出特殊的四重对称性.X射线线性二色谱及第一性原理计算表明,超晶格中磁各向异性的变化与界面处轨道重构有关:随着SMO厚度的增加,超晶格中电子将由择优占据面内轨道转变为择优占据面外轨道.本实验提出了一种调控磁各向异性的新方法,为异质结中磁性质的控制及新现象的产生提供了新的研究思路.
作者
Guowei Zhou
Huihui Ji
Zhi Yan
Miming Cai
Penghua Kang
Jun Zhang
Jingdi Lu
Jinxing Zhang
Jingsheng Chen
Xiaohong Xu
周国伟;姬慧慧;严志;蔡米铭;康鹏华;张军;鲁京迪;张金星;陈景升;许小红(School of Chemistry and Materials Science of Shanxi Normal University&Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education,Linfen 041004,China;Research Institute of Materials Science of Shanxi Normal University&Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and Technology,Linfen 041004,China;Department of Materials Science and Engineering,National University of Singapore,Singapore 117575,Singapore;Department of Physics,Beijing Normal University,Beijing 100875,China)
基金
financially supported by the National Natural Science Foundation of China(51901118,51871137,12174237,and 52171183)
the 1331 Engineering of Shanxi Province
the Research Project Supported by Shanxi Scholarship Council of China(2021-093)
the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(2020L0237)。
