Xie Qidong, Lin Weinan, Liang Jinghua, Zhou Hengan, Waqar Moaz, Lin Ming, Teo Siew Lang, Chen Hao, Lu Xiufang, Shu Xinyu, Liu Liang, Chen Shaohai, Zhou Chenghang, Chai Jianwei, Yang Ping, Loh Kian Ping, Wang John, Jiang Wanjun, Manchon Aurelien, Yang Hongxin, Chen Jingsheng
Department of Materials Science and Engineering, National University of Singapore, Singapore, 117575, Singapore.
Department of physics, Xiamen University, Xiamen, 361005, China.
Adv Mater. 2022 Aug;34(33):e2109449. doi: 10.1002/adma.202109449. Epub 2022 Jul 14.
Van der Waals materials are attracting great attention in the field of spintronics due to their novel physical properties. For example, they are utilized as spin-current generating materials in spin-orbit torque (SOT) devices, which offers an electrical way to control the magnetic state and is promising for future low-power electronics. However, SOTs have mostly been demonstrated in vdW materials with strong spin-orbit coupling (SOC). Here, the observation of a current-induced SOT in the h-BN/SrRuO bilayer structure is reported, where the vdW material (h-BN) is an insulator with negligible SOC. Importantly, this SOT is strong enough to induce the switching of the perpendicular magnetization in SrRuO . First-principles calculations suggest a giant Rashba effect at the interface between vdW material and SrRuO (110) thin film, which leads to the observed SOT based on a simplified tight-binding model. Furthermore, it is demonstrated that the current-induced magnetization switching can be modulated by the electric field. This study paves the way for exploring the current-induced SOT and magnetization switching by integrating vdW materials with ferromagnets.
范德华材料因其新颖的物理性质在自旋电子学领域引起了极大关注。例如，它们被用作自旋轨道矩（SOT）器件中的自旋电流产生材料，这提供了一种电控制磁状态的方法，对未来的低功耗电子学很有前景。然而，SOT大多在具有强自旋轨道耦合（SOC）的范德华材料中得到证明。在此，报道了在h-BN/SrRuO双层结构中电流诱导SOT的观测结果，其中范德华材料（h-BN）是一种具有可忽略SOC的绝缘体。重要的是，这种SOT足够强，足以诱导SrRuO中垂直磁化的切换。第一性原理计算表明，在范德华材料与SrRuO（110）薄膜的界面处存在巨大的Rashba效应，基于简化的紧束缚模型导致了观测到的SOT。此外，还证明了电流诱导的磁化切换可以通过电场进行调制。这项研究为通过将范德华材料与铁磁体集成来探索电流诱导的SOT和磁化切换铺平了道路。
