Time-resolved x-ray microscopy of spin-torque-induced magnetic vortex gyration
Time-resolved x-ray microscopy of spin-torque-induced magnetic vortex gyration
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DOI：
10.1103/physrevlett.100.176601
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发表时间：
2008-05-02
影响因子：
8.6
通讯作者：
Stoll, Hermann
中科院分区：
文献类型：
--
作者：
Bolte, Markus;Meier, Guido;Stoll, Hermann
时间分辨x射线显微镜是用来成像的影响，交变高密度电流的铁磁涡旋的磁化动力学。在微米级的坡莫合金方块中观察到了自旋力矩诱导的涡旋旋转。在具有不同手性的结构中的旋转的相位进行比较的分析模型和微磁模拟，考虑到交替的自旋极化电流和电流的奥斯特场。在我们的情况下，由于自旋转移扭矩的驱动力是约70%的总激励，而其余部分来自电流的奥斯特场。这一发现对使用自旋扭矩驱动的磁化切换和畴壁运动的磁存储器件具有影响。
Time-resolved x-ray microscopy is used to image the influence of alternating high-density currents on the magnetization dynamics of ferromagnetic vortices. Spin-torque-induced vortex gyration is observed in micrometer-sized permalloy squares. The phases of the gyration in structures with different chirality are compared to an analytical model and micromagnetic simulations, considering both alternating spin-polarized currents and the current's Oersted field. In our case the driving force due to spin-transfer torque is about 70% of the total excitation while the remainder originates from the current's Oersted field. This finding has implications to magnetic storage devices using spin-torque driven magnetization switching and domain-wall motion.