Dai Hongwei, Cai Menghao, Hao Qinghua, Liu Qingbo, Xing Yuntong, Chen Hongjing, Chen Xiaodie, Wang Xia, Fu Hua-Hua, Han Junbo
Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, 430074, China.
Department of Physics, Huazhong University of Science and Technology, Wuhan, 430074, China.
ACS Nano. 2022 Aug 23;16(8):12437-12444. doi: 10.1021/acsnano.2c03626. Epub 2022 Jul 28.
Two-dimensional (2D) magnets are crucial in the construction of 2D magnetic and spintronic devices. Many devices, including spin valves and multiple tunneling junctions, have been developed by vertically stacking 2D magnets with other functional blocks. However, owing to limited local interactions at the interfaces, the device structures are typically extremely complex. To solve this problem, the nonlocal manipulation of magnetism may be a good solution. In this study, we use the magneto-optical Kerr effect technique to demonstrate the nonlocal manipulation of magnetism in an itinerant 2D ferromagnet, FeGeTe (FGT), whose magnetism can be manipulated an antiferromagnet/ferromagnet interface or a current-induced spin-orbital torque placed distant from the local site. It is discovered that the coupling of a small piece of MnPS (∼40 μm) with FGT can significantly enhance the coercive field and emergence of exchange bias in the entire FGT flake (∼2000 μm). Moreover, FGT flakes with different thicknesses have the same coercive field at low temperatures if they are coupled together. Our study provides an understanding of the basic magnetism of 2D itinerant ferromagnets as well as opportunities for engineering magnetism with an additional degree of freedom.
二维（2D）磁体在二维磁性和自旋电子器件的构建中至关重要。许多器件，包括自旋阀和多个隧道结，都是通过将二维磁体与其他功能块垂直堆叠而开发的。然而，由于界面处局部相互作用有限，器件结构通常极其复杂。为了解决这个问题，磁性的非局部操纵可能是一个很好的解决方案。在本研究中，我们使用磁光克尔效应技术来证明在巡游二维铁磁体FeGeTe（FGT）中磁性的非局部操纵，其磁性可以通过反铁磁体/铁磁体界面或远离局部位置的电流诱导自旋轨道转矩来操纵。研究发现，一小片MnPS（约40μm）与FGT的耦合可以显著增强整个FGT薄片（约2000μm）的矫顽场和交换偏置的出现。此外，如果将不同厚度的FGT薄片耦合在一起，它们在低温下具有相同的矫顽场。我们的研究提供了对二维巡游铁磁体基本磁性的理解，以及利用额外自由度进行磁性工程的机会。
