Controlled nonlinear magnetic damping in spin-Hall nano-devices
Controlled nonlinear magnetic damping in spin-Hall nano-devices
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DOI：
10.1038/s41467-019-13246-7
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发表时间：
2019-11-18
影响因子：
16.6
通讯作者：
Demidov, Vladislav E.
中科院分区：
文献类型：
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作者：
Divinskiy, Boris;Urazhdin, Sergei;Demidov, Vladislav E.
大幅度磁化动力学比低幅度线性磁化要复杂得多，这是因为不可避免地出现了非线性。其中最基本的非线性现象之一就是非线性阻尼增强，这对磁性纳米器件的运行和效率提出了严格的限制。具体地说，非线性阻尼阻止了由自旋电流注入空间扩展的磁区所驱动的相干磁化自振荡的激发。在这里，我们提出并实验证明了非线性阻尼可以由磁化进动的椭圆度来控制。通过平衡对各向异性的不同贡献，我们最小化了椭圆度，并实现了由空间扩展的自旋电流注入到微观磁盘中所驱动的相干磁化振荡。我们的结果为实现有效的自旋电流驱动的有源自旋和磁子器件提供了一条途径。
Large-amplitude magnetization dynamics is substantially more complex compared to the low-amplitude linear regime, due to the inevitable emergence of nonlinearities. One of the fundamental nonlinear phenomena is the nonlinear damping enhancement, which imposes strict limitations on the operation and efficiency of magnetic nanodevices. In particular, nonlinear damping prevents excitation of coherent magnetization auto-oscillations driven by the injection of spin current into spatially extended magnetic regions. Here, we propose and experimentally demonstrate that nonlinear damping can be controlled by the ellipticity of magnetization precession. By balancing different contributions to anisotropy, we minimize the ellipticity and achieve coherent magnetization oscillations driven by spatially extended spin current injection into a microscopic magnetic disk. Our results provide a route for the implementation of efficient active spintronic and magnonic devices driven by spin current.