Li Yang, Li Yan, Sun Rui, Liu Jia-Nan, Li Na, Yang Xu, Gong Zi-Zhao, Xie Zong-Kai, He Wei, Zhang Xiang-Qun, Cheng Zhao-Hua
State Key Laboratory of Magnetism and Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
J Phys Condens Matter. 2021 Apr 21;33(17). doi: 10.1088/1361-648X/abe265.
The determination of intrinsic Gilbert damping is one of the central interests in the field of spintronics. However, some external factors in magnetic films tend to play a remarkable role in the magnetization dynamics. Here, we present a comprehensive study of the magnetic relaxation in ferromagnetic films with various in-plane magnetic anisotropy via ferromagnetic resonance technique. We find that the magnetic drag effect can result in the resonant linewidth broadening and the nonlinear dependence of linewidth on frequency stemming from field-magnetization misalignment. As a result, this could lead to the imprecise extraction of the key dynamic parameter-Gilbert damping and cause the confusing behaviors of ultra-low and anisotropic damping in thin films and multi-layers with high magnetic anisotropy. Our results provide a crucial way for the accurately quantitative estimation of the Gilbert damping in spintronics measurements.
确定本征吉尔伯特阻尼是自旋电子学领域的核心研究兴趣之一。然而，磁性薄膜中的一些外部因素往往在磁化动力学中起着显著作用。在此，我们通过铁磁共振技术对具有各种面内磁各向异性的铁磁薄膜中的磁弛豫进行了全面研究。我们发现，磁拖曳效应会导致共振线宽展宽以及线宽对频率的非线性依赖，这源于场与磁化的失准。因此，这可能导致关键动态参数——吉尔伯特阻尼的提取不准确，并在具有高磁各向异性的薄膜和多层膜中引发超低和各向异性阻尼的混淆行为。我们的结果为在自旋电子学测量中准确量化估计吉尔伯特阻尼提供了关键方法。
