MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
Institute of Solid State Physics, Vienna University of Technology, A-1040 Vienna, Austria.
Nat Mater. 2016 Apr;15(4):425-31. doi: 10.1038/nmat4579. Epub 2016 Mar 7.
Controlled in-plane rotation of the magnetic easy axis in manganite heterostructures by tailoring the interface oxygen network could allow the development of correlated oxide-based magnetic tunnelling junctions with non-collinear magnetization, with possible practical applications as miniaturized high-switching-speed magnetic random access memory (MRAM) devices. Here, we demonstrate how to manipulate magnetic and electronic anisotropic properties in manganite heterostructures by engineering the oxygen network on the unit-cell level. The strong oxygen octahedral coupling is found to transfer the octahedral rotation, present in the NdGaO3 (NGO) substrate, to the La2/3Sr1/3MnO3 (LSMO) film in the interface region. This causes an unexpected realignment of the magnetic easy axis along the short axis of the LSMO unit cell as well as the presence of a giant anisotropic transport in these ultrathin LSMO films. As a result we possess control of the lateral magnetic and electronic anisotropies by atomic-scale design of the oxygen octahedral rotation.
通过调整界面氧网络,可以控制钙钛矿锰氧化物异质结构中磁易轴的面内旋转,这可能为开发具有非共线磁化的关联氧化物磁隧道结铺平道路,这种磁隧道结在作为小型化高速磁随机存取存储器(MRAM)器件方面具有潜在的实际应用。在这里,我们展示了如何通过在单元水平上设计氧网络来操纵锰氧化物异质结构中的磁各向异性和电子各向异性。研究发现,强氧八面体耦合将 NdGaO3(NGO)衬底中存在的八面体旋转转移到界面区域的 La2/3Sr1/3MnO3(LSMO)薄膜中。这导致磁易轴沿着 LSMO 单元短轴的意外重新排列,以及这些超薄 LSMO 薄膜中存在巨大的各向异性输运。因此,通过原子尺度设计氧八面体旋转,我们可以控制横向磁各向异性和电子各向异性。