Han Jiahao, Richardella A, Siddiqui Saima A, Finley Joseph, Samarth N, Liu Luqiao
Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Phys Rev Lett. 2017 Aug 18;119(7):077702. doi: 10.1103/PhysRevLett.119.077702.
The strongly spin-momentum coupled electronic states in topological insulators (TI) have been extensively pursued to realize efficient magnetic switching. However, previous studies show a large discrepancy of the charge-spin conversion efficiency. Moreover, current-induced magnetic switching with TI can only be observed at cryogenic temperatures. We report spin-orbit torque switching in a TI-ferrimagnet heterostructure with perpendicular magnetic anisotropy at room temperature. The obtained effective spin Hall angle of TI is substantially larger than the previously studied heavy metals. Our results demonstrate robust charge-spin conversion in TI and provide a direct avenue towards applicable TI-based spintronic devices.
拓扑绝缘体（TI）中强自旋动量耦合的电子态已被广泛研究，以实现高效的磁开关。然而，先前的研究表明电荷-自旋转换效率存在很大差异。此外，TI的电流诱导磁开关只能在低温下观察到。我们报道了在室温下具有垂直磁各向异性的TI-铁氧体异质结构中的自旋轨道矩开关。所获得的TI有效自旋霍尔角显著大于先前研究的重金属。我们的结果证明了TI中稳健的电荷-自旋转换，并为基于TI的自旋电子器件的应用提供了一条直接途径。
