Microelectronics Group, Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, UK.
Institute of Physics, ASCR, v.v.i., Cukrovarnicka 10, 16253 Praha 6, Czech Republic.
Nat Commun. 2015 Mar 31;6:6730. doi: 10.1038/ncomms7730.
Recently discovered relativistic spin torques induced by a lateral current at a ferromagnet/paramagnet interface are a candidate spintronic technology for a new generation of electrically controlled magnetic memory devices. The focus of our work is to experimentally disentangle the perceived two model physical mechanisms of the relativistic spin torques, one driven by the spin-Hall effect and the other one by the inverse spin-galvanic effect. Here, we show a vector analysis of the torques in a prepared epitaxial transition-metal ferromagnet/semiconductor-paramagnet single-crystal structure by means of the all-electrical ferromagnetic resonance technique. By choice of our structure in which the semiconductor paramagnet has a Dresselhaus crystal inversion asymmetry, the system is favourable for separating the torques due to the inverse spin-galvanic effect and spin-Hall effect mechanisms into the field-like and antidamping-like components, respectively. Since they contribute to distinct symmetry torque components, the two microscopic mechanisms do not compete but complement each other in our system.
最近在铁磁体/顺磁体界面上由横向电流引起的相对论自旋扭矩是新一代电控制磁存储设备的候选自旋电子技术。我们工作的重点是通过实验分离出相对论自旋扭矩的两种被认为的物理机制，一种由自旋霍尔效应驱动，另一种由反自旋-几何效应驱动。在这里，我们通过全电铁磁共振技术对制备的外延过渡金属铁磁体/半导体顺磁单晶结构中的扭矩进行了矢量分析。通过选择我们的结构，其中半导体顺磁体具有 Dresselhaus 晶体反演不对称性，该系统有利于将由于反自旋-几何效应和自旋霍尔效应机制引起的扭矩分别分离为场类似和反阻尼类似分量。由于它们贡献了不同的对称扭矩分量，因此这两个微观机制在我们的系统中不是竞争关系，而是互补关系。
