Perpendicular magnetization switching by large spin-orbit torques from sputtered Bi2Te3
Perpendicular magnetization switching by large spin-orbit torques from sputtered Bi2Te3
复制标题
溅射 Bi2Te3 大自旋轨道扭矩的垂直磁化切换
DOI：
10.1088/1674-1056/ab9439
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发表时间：
2020-07-01
影响因子：
1.7
通讯作者：
Zhao, Weisheng
中科院分区：
文献类型：
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作者：
Zheng, Zhenyi;Zhang, Yue;Zhao, Weisheng
自旋轨道矩（SOT）效应被认为是一种有效的磁化转换方式，可以激发各种高性能的自旋电子器件。最近，拓扑绝缘体（TI）得到了广泛的关注，因为它们被证明即使在室温下也保持大的有效自旋霍尔角（theta（eff）（SH））。然而，分子束外延（MBE）作为一种精确的沉积方法，需要保证TI的良好表面状态，这阻碍了TI的工业应用的前景。本文研究了磁控溅射法生长的Bi（2）Te（3）薄膜在具有垂直磁各向异性的CoTb铁磁合金异质结中的SOT效应。通过谐波霍尔测量，在室温下获得了高的SOT效率（8.7 ± 0.9 Oe/（10（9）A/m（2）））和大的θ（eff）（SH）（3.3 ± 0.3）。此外，我们还观察到了超低的临界开关电流密度（9.7 × 10（9）A/m（2））。通过与不同溅射SOT源的比较，研究了溅射Bi（2）Te（3）薄膜的低功率特性。我们的工作可能会提供一个替代利用硫属化物作为一个现实的和有效的SOT源在未来的自旋电子器件。
Spin-orbit torque (SOT) effect is considered as an efficient way to switch the magnetization and can inspire various high-performance spintronic devices. Recently, topological insulators (TIs) have gained extensive attention, as they are demonstrated to maintain a large effective spin Hall angle (theta(eff)(SH)), even at room temperature. However, molecular beam epitaxy (MBE), as a precise deposition method, is required to guarantee favorable surface states of TIs, which hinders the prospect of TIs towards industrial application. In this paper, we demonstrate that Bi(2)Te(3)films grown by magnetron sputtering can provide a notable SOT effect in the heterostructure with perpendicular magnetic anisotropy CoTb ferrimagnetic alloy. By harmonic Hall measurement, a high SOT efficiency (8.7 +/- 0.9 Oe/(10(9)A/m(2))) and a large theta(eff)(SH)(3.3 +/- 0.3) are obtained at room temperature. Besides, we also observe an ultra-low critical switching current density (9.7x10(9)A/m(2)). Moreover, the low-power characteristic of the sputtered Bi(2)Te(3)film is investigated by drawing a comparison with different sputtered SOT sources. Our work may provide an alternative to leverage chalcogenides as a realistic and efficient SOT source in future spintronic devices.