Spin-orbit torque induced magnetization switching in nano-scale Ta/CoFeB/MgO
Spin-orbit torque induced magnetization switching in nano-scale Ta/CoFeB/MgO
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DOI：
10.1063/1.4926371
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发表时间：
2015-07
影响因子：
4
通讯作者：
Chaoliang Zhang;S. Fukami;Hirotoshi Sato;F. Matsukura;H. Ohno
中科院分区：
文献类型：
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作者：
Chaoliang Zhang;S. Fukami;Hirotoshi Sato;F. Matsukura;H. Ohno
我们研究了在具有垂直易轴的Ta/CoFeB/MgO结构中，自旋轨道扭矩诱导的磁化翻转对器件尺寸的依赖性。器件从微米尺寸的线缩小到80纳米的点，导致阈值电流密度Jth增加了一个数量级，然而当器件尺寸进一步减小到30纳米时，Jth仅略微增加。当电流脉冲宽度从100毫秒减小到3纳秒时，未观察到Jth的显著增加。我们揭示，对于尺寸减小的器件中的翻转，宏观自旋模型能够合理地很好解释，该模型包含了类似Slonczewski扭矩和类场扭矩的效应。
We study the device size dependence of spin-orbit torque induced magnetization switching in a Ta/CoFeB/MgO structure with perpendicular easy axis. The miniaturization of the device from micrometer-sized wire to 80-nm dot results in the increase of the threshold current density Jth by one order, whereas Jth increases only slightly with further reducing the device size down to 30 nm. No significant increase in Jth is seen, as the current pulse width decreases from 100 ms down to 3 ns. We reveal that the switching in devices at reduced size is reasonably well explained by the macrospin model, in which the effects of both the Slonczewski-like torque and field-like torque are included.