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用反应溅射方法制备了Fe R O(R =Hf,Nd ,Dy)薄膜 ,并在 4 0 0℃时对样品进行退火处理 ,x射线衍射和电子衍射结果显示纳米量级的Fe晶粒镶嵌在非晶氧化物基质中 .用面内铁磁共振技术仔细测量了样品的共振吸收谱 ,并分析了局域磁化强度Ms 与晶粒尺寸的关系 .制备态样品呈现出显著的面内单轴各向异性 ,退火后单轴各向异性显著减弱 ,取而代之的是较弱的磁晶各向异性 .利用公式 (ω γ) 2 =(Hres+HK) (Hres+HK +4πMs)求出局域磁化强度Ms,它随晶粒尺寸减小而减小 ,在晶粒尺寸为 5nm时仅约为Fe体材料饱和磁化强度的 30 % .局域磁化强度与根据Fe的体积百分比算出的体磁化强度相比偏小 ,并与晶粒尺寸的倒数呈线性关系 ,说明在晶粒表面存在较强的磁矩钉扎效应 .
Fe RO (R = Hf, Nd, Dy) thin films were prepared by reactive sputtering. The samples were annealed at 400 ℃. The results of X-ray diffraction and electron diffraction showed that nano- Amorphous oxide matrix. The resonance absorption spectra of the samples were carefully measured by in-plane ferromagnetic resonance technique and the relationship between the local magnetization Ms and the grain size was analyzed. The prepared samples showed significant in-plane uniaxial Anisotropy, uniaxial anisotropy after annealing significantly weakened, replaced by a weak magnetocrystalline anisotropy by using the formula (ω γ) 2 = (Hres + HK) (Hres + HK + 4πMs) to find the local magnetization The intensity Ms, which decreases as the grain size decreases, is only about 30% of the saturation magnetization of the Fe bulk material at a grain size of 5nm.The local magnetization is related to the volume fraction of bulk magnetization based on the volume fraction of Fe Is smaller than that of the grain size, and is linear with the reciprocal of the grain size, indicating that there is a strong magnetic moment pinning effect on the grain surface.