School of Materials Science and Engineering, University of Science and Technology Beijing, 100083, Beijing, China.
Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03, Singapore, 138634, Republic of Singapore.
Nat Commun. 2023 May 19;14(1):2871. doi: 10.1038/s41467-023-38550-1.
Manipulating spin polarization orientation is challenging but crucial for field-free spintronic devices. Although such manipulation has been demonstrated in a limited number of antiferromagnetic metal-based systems, the inevitable shunting effects from the metallic layer can reduce the overall device efficiency. In this study, we propose an antiferromagnetic insulator-based heterostructure NiO/Ta/Pt/Co/Pt for such spin polarization control without any shunting effect in the antiferromagnetic layer. We show that zero-field magnetization switching can be realized and is related to the out-of-plane component of spin polarization modulated by the NiO/Pt interface. The zero-field magnetization switching ratio can be effectively tuned by the substrates, in which the easy axis of NiO can be manipulated by the tensile or compressive strain from the substrates. Our work demonstrates that the insulating antiferromagnet based heterostructure is a promising platform to enhance the spin-orbital torque efficiency and achieve field-free magnetization switching, thus opening an avenue towards energy-efficient spintronic devices.
操控自旋极化方向极具挑战性，但对于无场自旋电子学器件而言至关重要。尽管这种操控已经在有限数量的反铁磁金属基系统中得到了证明，但金属层不可避免的分流效应会降低整体器件效率。在这项研究中，我们提出了一种基于反铁磁绝缘体的异质结构 NiO/Ta/Pt/Co/Pt，用于在反铁磁层中不存在任何分流效应的情况下进行这种自旋极化控制。我们表明，可以实现零场磁化开关，这与由 NiO/Pt 界面调制的自旋极化的面外分量有关。零场磁化开关比可以通过衬底有效地进行调节，其中 NiO 的易磁化轴可以通过衬底的拉伸或压缩应变来操纵。我们的工作表明，基于绝缘反铁磁体的异质结构是增强自旋轨道扭矩效率并实现无场磁化开关的有前途的平台，从而为节能型自旋电子学器件开辟了一条道路。
