Large voltage-controlled magnetic anisotropy in the SrTiO3/Fe/Cu structure
Large voltage-controlled magnetic anisotropy in the SrTiO3/Fe/Cu structure
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SrTiO3/Fe/Cu 结构中的大电压控制磁各向异性
DOI：
10.1063/1.4996275
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发表时间：
2017
影响因子：
4
通讯作者：
Weisheng Zhao
中科院分区：
文献类型：
--
作者：
Shouzhong Peng;Sai Li;Wang Kang;Jiaqi Zhou;Na Lei;Youguang Zhang;Hongxin Yang;Xiang Li;Pedram Khalili Amiri;Kang L. Wang;Weisheng Zhao
利用第一性原理计算研究了钛酸锶（SrTiO 3）基结构的磁各向异性和压控磁各向异性（VCMA）。据发现，SrTiO 3/Fe/Cu引起的界面垂直磁各向异性（PMA）为1.3 mJ/m2。更重要的是，该结构的VCMA系数比MgO基对应物的VCMA系数大37%。通过解析VCMA对各原子层和各轨道杂化的影响，阐明了其微观机理。我们表明，VCMA效应并不局限于第一个铁单层的SrTiO 3/Fe界面，但延伸到第二和第三个铁单层。这些现象的起因可以用电场作用下轨道占有率重新分布引起的各轨道杂化对PMA贡献的变化来解释。
First-principles calculations are performed to investigate the magnetic anisotropy and voltage-controlled magnetic anisotropy (VCMA) in the strontium titanate (SrTiO3)-based structure. It is found that SrTiO3/Fe/Cu gives rise to an interfacial perpendicular magnetic anisotropy (PMA) of 1.3 mJ/m2. More importantly, the VCMA coefficient of this structure is 37% larger than that of the MgO-based counterpart. The microscopic mechanism is elucidated by resolving the VCMA effect to each atomic layer and each orbital hybridization. We demonstrate that the VCMA effect is not confined at the first Fe monolayer of the SrTiO3/Fe interface but extends into the second and third Fe monolayers. The origin of these phenomena can be explained with the changes of contributions to PMA from each orbital hybridization induced by redistributions of orbital occupancy under an electric field.