Go Dongwook, Sallermann Moritz, Lux Fabian R, Blügel Stefan, Gomonay Olena, Mokrousov Yuriy
Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany.
Institute of Physics, Johannes Gutenberg University Mainz, 55099 Mainz, Germany.
Phys Rev Lett. 2022 Aug 26;129(9):097204. doi: 10.1103/PhysRevLett.129.097204.
We propose a concept of noncollinear spin current, whose spin polarization varies in space even in nonmagnetic crystals. While it is commonly assumed that the spin polarization of the spin Hall current is uniform, asymmetric local crystal potential generally allows the spin polarization to be noncollinear in space. Based on microscopic considerations, we demonstrate that such noncollinear spin Hall currents can be observed, for example, in layered Kagome Mn_{3}X (X=Ge, Sn) compounds. Moreover, by referring to atomistic spin dynamics simulations we show that noncollinear spin currents can be used to switch the chiral spin texture of Mn_{3}X in a deterministic way even in the absence of an external magnetic field. Our theoretical prediction can be readily tested in experiments, which will open a novel route toward electric control of complex spin structures in noncollinear antiferromagnets.
我们提出了一种非共线自旋电流的概念，即使在非磁性晶体中，其自旋极化也会随空间变化。虽然通常认为自旋霍尔电流的自旋极化是均匀的，但不对称的局部晶体势通常会使自旋极化在空间中呈非共线状态。基于微观考虑，我们证明了例如在层状 Kagome 锰化合物 Mn₃X（X = Ge，Sn）中可以观察到这种非共线自旋霍尔电流。此外，通过参考原子自旋动力学模拟，我们表明即使在没有外部磁场的情况下，非共线自旋电流也可用于以确定性方式切换 Mn₃X 的手性自旋纹理。我们的理论预测可以很容易地在实验中得到验证，这将为非共线反铁磁体中复杂自旋结构的电控制开辟一条新途径。
