Yang Hongxin, Chen Gong, Cotta Alexandre A C, N'Diaye Alpha T, Nikolaev Sergey A, Soares Edmar A, Macedo Waldemar A A, Liu Kai, Schmid Andreas K, Fert Albert, Chshiev Mairbek
Univ. Grenoble Alpes, CEA, CNRS, Grenoble INP, INAC-SPINTEC, Grenoble, France.
Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, Palaiseau, France.
Nat Mater. 2018 Jul;17(7):605-609. doi: 10.1038/s41563-018-0079-4. Epub 2018 May 28.
The possibility of utilizing the rich spin-dependent properties of graphene has attracted much attention in the pursuit of spintronics advances. The promise of high-speed and low-energy-consumption devices motivates the search for layered structures that stabilize chiral spin textures such as topologically protected skyrmions. Here we demonstrate that chiral spin textures are induced at graphene/ferromagnetic metal interfaces. Graphene is a weak spin-orbit coupling material and is generally not expected to induce a sufficient Dzyaloshinskii-Moriya interaction to affect magnetic chirality. We demonstrate that indeed graphene does induce a type of Dzyaloshinskii-Moriya interaction due to the Rashba effect. First-principles calculations and experiments using spin-polarized electron microscopy show that this graphene-induced Dzyaloshinskii-Moriya interaction can have a similar magnitude to that at interfaces with heavy metals. This work paves a path towards two-dimensional-material-based spin-orbitronics.
在追求自旋电子学进展的过程中,利用石墨烯丰富的自旋相关特性的可能性已引起了广泛关注。高速和低能耗器件的前景促使人们寻找能够稳定手性自旋纹理(如拓扑保护的斯格明子)的层状结构。在此,我们证明了在石墨烯/铁磁金属界面会诱导出手性自旋纹理。石墨烯是一种弱自旋轨道耦合材料,通常预计不会诱导出足够的Dzyaloshinskii-Moriya相互作用来影响磁手性。我们证明,由于Rashba效应,石墨烯确实会诱导出一种Dzyaloshinskii-Moriya相互作用。第一性原理计算以及使用自旋极化电子显微镜的实验表明,这种由石墨烯诱导的Dzyaloshinskii-Moriya相互作用的强度可以与重金属界面处的相互作用强度相当。这项工作为基于二维材料的自旋轨道ronics铺平了道路。