In this letter, we present a numerical approach to obtain the ferromagnetic resonance spectra of micrometer- and nanometer-sized magnetic elements by micromagnetic simulations. By mimicking common experimental conditions, we applied a static magnetic field and used a linearly polarized oscillating magnetic field to excite magnetization dynamics. A continuous single-frequency excitation is utilized, which permits the study of the steady-state dynamics in the space and time domain. This gives direct access to resonance fields, linewidths, and relative amplitudes as observed in the experiments, which is not easily accessible in pulsed schemes and allows for a one-to-one identification between simulation and experiment. Similar to numerical approaches using pulsed excitations, the phases, ellipticity, and spatial mode profiles of the spin-wave excitations may also be accessed. Using large excitation powers, we then showcase that one can additionally study nonlinear responses by this method, such as the nonlinear shift of the resonance fields and the foldover of the absorption lines. Since the dynamic susceptibility is directly determined from standard outputs of common micromagnetic codes, the presented method is robust, efficient, and easy-to-use, adding to its practical importance.

中文翻译：

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纳米元素中的数字铁磁共振实验

在这封信中，我们提出了一种通过微磁模拟来获得微米级和纳米级磁性元件的铁磁共振光谱的数值方法。通过模拟常见的实验条件，我们施加了静磁场，并使用了线性极化振荡磁场来激发磁化动力学。利用连续的单频激励，可以研究时空中的稳态动力学。这样可以直接访问实验中观察到的共振场，线宽和相对幅度，这在脉冲方案中不容易获得，并且可以在仿真和实验之间进行一对一的识别。与使用脉冲激励的数值方法相似，相位，椭圆率，自旋波激发的空间模式分布图也可以访问。然后，我们使用大的激励功率来证明，人们还可以通过这种方法来研究非线性响应，例如共振场的非线性位移和吸收线的折叠。由于动态磁化率是直接根据常见微磁码的标准输出确定的，因此所提出的方法是健壮，高效且易于使用的，这增加了其实际重要性。