论文标题
旋转轨道的强烈变化，具有相对自旋松弛率
Strong variation of spin-orbit torques with relative spin relaxation rates in ferrimagnets
论文作者
论文摘要
自旋轨道扭矩（SOT）已被广泛理解为自旋的界面转移，它与磁层的散装特性无关。在这里，我们报告说，在接近磁补偿点时作用于铁磁性FEXTB1-X层上的SOT会减小和消失，因为自旋转移速率比由于自旋轨道散射而导致的自旋松弛速率降低了向晶体晶格的速度慢。这些结果表明，磁性层中竞争性自旋松弛过程的相对速率在确定SOT的强度方面起着关键作用，这为铁磁和补偿系统中的各种甚至似乎令人困惑的SOT现象提供了统一的理解。我们的工作表明，应将磁铁内的自旋轨道散射最小化，以获得有效的SOT设备。我们还发现，铁磁合金（例如FexTB1-X）的界面旋转电导率与3D铁磁体的界面旋转电导（例如FEXTB1-X）一样大，并且对磁补偿程度不敏感。
Spin-orbit torques (SOTs) have been widely understood as an interfacial transfer of spin that is independent of the bulk properties of the magnetic layer. Here, we report that SOTs acting on ferrimagnetic FexTb1-x layers decrease and vanish upon approaching the magnetic compensation point because the rate of spin transfer to the magnetization becomes slower than the rate of spin relaxation into the crystal lattice due to spin-orbit scattering. These results indicate that the relative rates of competing spin relaxation processes within magnetic layers play a critical role in determining the strength of SOTs, which provides a unified understanding for the diverse and even seemingly puzzling SOT phenomena in ferromagnetic and compensated systems. Our work indicates that spin-orbit scattering within the magnet should be minimized for efficient SOT devices. We also find that the interfacial spin-mixing conductance of interfaces of ferrimagnetic alloys (such as FexTb1-x) is as large as that of 3d ferromagnets and insensitive to the degree of magnetic compensation.
