Nanoscale interface confinement of ultrafast spin transfer torque driving non-uniform spin dynamics.
Nanoscale interface confinement of ultrafast spin transfer torque driving non-uniform spin dynamics.
复制标题
DOI：
10.1038/ncomms15007
复制
发表时间：
2017-04-13
影响因子：
16.6
通讯作者：
Melnikov A
中科院分区：
文献类型：
--
作者：
Razdolski I;Alekhin A;Ilin N;Meyburg JP;Roddatis V;Diesing D;Bovensiepen U;Melnikov A
自旋电子学在过去几十年中产生了广泛的影响，因为它通过自旋而不是电流来传递信息。它的进一步发展需要结合亚纳米空间和飞秒时间范围的自旋动力学特征时间尺度的小型化和减少。这些需求转移的关注焦点对基本的开放性问题的飞秒自旋电流（SC）脉冲与铁磁体（FM）的相互作用。由超短SC脉冲施加在FM上的脉冲自旋转移力矩的时空特性打开了用于探测非均匀磁化动力学的时域。在这里，我们采用激光产生的超短SC脉冲驱动超快自旋动力学FM和分析其瞬态本地源。注入FM的横向自旋激发不均匀的高频自旋动力学高达0.6太赫兹，表明FM磁化的扰动被限制在2纳米。对超快自旋动力学的基本理解对于自旋电子学的应用是至关重要的。在这里，作者展示了一种超快技术来探索自旋转移矩触发的Fe/Au/Fe多层膜中的非均匀太赫兹自旋动力学。
Spintronics had a widespread impact over the past decades due to transferring information by spin rather than electric currents. Its further development requires miniaturization and reduction of characteristic timescales of spin dynamics combining the sub-nanometre spatial and femtosecond temporal ranges. These demands shift the focus of interest towards the fundamental open question of the interaction of femtosecond spin current (SC) pulses with a ferromagnet (FM). The spatio-temporal properties of the impulsive spin transfer torque exerted by ultrashort SC pulses on the FM open the time domain for probing non-uniform magnetization dynamics. Here we employ laser-generated ultrashort SC pulses for driving ultrafast spin dynamics in FM and analysing its transient local source. Transverse spins injected into FM excite inhomogeneous high-frequency spin dynamics up to 0.6 THz, indicating that the perturbation of the FM magnetization is confined to 2 nm. Fundamental understanding of ultrafast spin dynamics is crucial for spintronics applications. Here the authors demonstrate an ultrafast technique to explore the inhomogeneous THz spin dynamics in Fe/Au/Fe multilayers triggered by spin transfer torque.