The yttrium iron garnet（YIG） samples are prepared at different temperatures from 900℃ to 1300℃ by the metalorganic decomposition（MOD） method. The chemical composition and crystal structure of the samples are studied by scanning electron microscope（SEM）, XRD, and Mossbauer spectrometer. It is shown that the ratio of ferric ions on two types of sites, the octahedral and the tetrahedral, is increased with the sintering temperature. At 1300℃, the pure garnet phase has been obtained, in which the ferric ions ratio is 2：3 leading to the minimum magnetic coercivity and maximum saturation magnetization. These results provide a route to synthesize pure YIG materials as the basic materials used in various spintronics applications.
测量了FeCo薄膜在0.5-8 GHz频率范围内的复数磁导率谱，通过改变外加磁场 H ex 的方向、大小，研究磁导率虚部共振曲线出现的磁滞现象。验证了样品铁磁共振频率f r 的平方值随正向H ex 线性变化的规律；观察到 H ex 与样品磁化方向相反时，共振曲线的磁滞现象，尤其是 H ex 的值接近矫顽力H c时，共振曲线出现双峰，反映了铁磁薄膜中部分磁矩随着反向H ex 逐渐增大逐步翻转的磁化动力学过程。由铁磁共振公式拟合磁谱虚部曲线，计算了双共振峰出现时薄膜中磁矩发生翻转的比例。
