论文标题
旋转轨道扭矩来自基于PT的结构中的散装和界面
Spin-orbit torques originating from bulk and interface in Pt-based structures
论文作者
论文摘要
我们研究了基于PT的典型旋转型旋转扭矩。我们发现，在PT/Ni和Pt/Fe双层中，阻尼样扭矩效率取决于Pt层的厚度。我们还发现，尽管PT/Fe界面处的自旋记忆损失更强，但在PT/Ni和Pt/Fe双层中，阻尼样扭矩效率几乎相同。这些结果表明，尽管阻尼样扭矩的主要来源是PT层中的散装旋转霍尔效应，但由于PT/Fe双层中的界面产生了相当大的阻尼样扭矩，因此由于较强的界面旋转旋转轨道耦合。与阻尼状的扭矩相反，在PT/Ni和Pt/Fe双层中，其大小和符号几乎相同，磁场状的扭矩在很大程度上取决于铁磁层的选择。源自PT层中散装旋转大厅效应的场状扭矩的符号在PT/Ni和Pt/Fe Bilayers之间相反，这可以归因于旋转电导的假想部分的相反符号。这些结果表明，自旋轨道扭矩对FM层的电子结构非常敏感。
We investigated spin-orbit torques in prototypical Pt-based spintronic devices. We found that, in Pt/Ni and Pt/Fe bilayers, the damping-like torque efficiency depends on the thickness of the Pt layer. We also found that the damping-like torque efficiency is almost identical in the Pt/Ni and Pt/Fe bilayers despite the stronger spin memory loss at the Pt/Fe interface. These results suggest that although the dominant source of the damping-like torque is the bulk spin Hall effect in the Pt layer, a sizable damping-like torque is generated by the interface in the Pt/Fe bilayer due to the stronger interfacial spin-orbit coupling. In contrast to the damping-like torque, whose magnitude and sign are almost identical in the Pt/Ni and Pt/Fe bilayers, the field-like torque strongly depends on the choice of the ferromagnetic layer. The sign of the field-like torque originating from the bulk spin Hall effect in the Pt layer is opposite between the Pt/Ni and Pt/Fe bilayers, which can be attributed to the opposite sign of the imaginary part of the spin-mixing conductance. These results demonstrate that the spin-orbit torques are quite sensitive to the electronic structure of the FM layer.
