Benítez L Antonio, Savero Torres Williams, Sierra Juan F, Timmermans Matias, Garcia Jose H, Roche Stephan, Costache Marius V, Valenzuela Sergio O
Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Spain.
Universitat Autònoma de Barcelona, Bellaterra, Spain.
Nat Mater. 2020 Feb;19(2):170-175. doi: 10.1038/s41563-019-0575-1. Epub 2020 Jan 6.
Spin-orbit coupling stands as a powerful tool to interconvert charge and spin currents and to manipulate the magnetization of magnetic materials through spin-torque phenomena. However, despite the diversity of existing bulk materials and the recent advent of interfacial and low-dimensional effects, control of this interconversion at room temperature remains elusive. Here, we demonstrate strongly enhanced room-temperature spin-to-charge interconversion in graphene driven by the proximity of WS. By performing spin precession experiments in appropriately designed Hall bars, we separate the contributions of the spin Hall and the spin galvanic effects. Remarkably, their corresponding conversion efficiencies can be tailored by electrostatic gating in magnitude and sign, peaking near the charge neutrality point with an equivalent magnitude that is comparable to the largest efficiencies reported to date. Such electric-field tunability provides a building block for spin generation free from magnetic materials and for ultra-compact magnetic memory technologies.
自旋轨道耦合是一种强大的工具，可通过自旋扭矩现象实现电荷电流与自旋电流的相互转换，并操控磁性材料的磁化强度。然而，尽管现有体材料种类繁多，且近期出现了界面效应和低维效应，但在室温下控制这种相互转换仍然难以实现。在此，我们展示了由WS的近邻效应驱动的石墨烯中室温下自旋到电荷的相互转换显著增强。通过在精心设计的霍尔条中进行自旋进动实验，我们分离出自旋霍尔效应和自旋能斯特效应的贡献。值得注意的是，它们相应的转换效率可通过静电门控在大小和符号上进行调节，在电荷中性点附近达到峰值，其等效大小与迄今报道的最大效率相当。这种电场可调性为无需磁性材料的自旋产生以及超紧凑磁存储技术提供了一个构建模块。
