La_(0.67)Sr_(0.33)Mn_(1-y)Fe_yO_3(y=0,0.01,0.02,0.03)磁谱特性分析  

Magnetic Spectra Investigation of La_(0.67)Sr_(0.33)Mn_(1-y)Fe_yO_3(y=0,0.01,0.02,0.03)

作　　者：杨勇[1] 梁迪飞[1] 陈良[1] 邓龙江[1] 

机构地区：[1]电子科技大学电子薄膜与集成器件国家重点实验室隐身材料与技术教育部工程研究中心,四川成都610054

出　　处：《中国稀土学报》2008年第2期173-177,共5页Journal of the Chinese Society of Rare Earths

摘　　要：采用固相反应法制备了La0.67Sr0.33Mn1-yFeyO3(y=0,0.01,0.02,0.03)氧化物多晶样品,XRD测试表明形成了钙钛矿单相结构,铁掺入后材料的晶体结构没有明显变化。SEM测试表明样品晶粒大小为1~3μm,随着铁含量增加饱和磁化强度下降。样品室温磁导率(10 kHz^1.8 GHz)测试表明,复磁导率频谱曲线是典型的弛豫型谱线,且随铁离子含量增加其起始磁导率下降。同时通过最小二乘曲线拟合的方法分析了频谱曲线,分别给出了畴壁位移和磁畴转动对磁导率的贡献,结果表明,y=0,0.01的样品畴壁位移对磁导率的贡献大于畴转对磁导率的贡献,y=0.02,0.03的样品,畴转对磁导率的贡献大于畴壁位移的贡献。The polyerystalline samples with nominal composition La0.67Sr0.33Mn1-yFeyO3（y=0,0.01,0.02,0.03） were prepared by solid state reaction. The X-ray diffraction indicated that the obtained sampies were single phase with perovskite structure. The SEM images indicated that the average grain size of samples were 1 - 3 μm. The saturation of magnetization, permeability was decreased and there was no obvious structure deformation of crystal when doped with Fe. The frequency spectrum curves of complex permeability （ 10 KHz - 1.8 GHz） at room temperature ex- hibited a relaxation character and were discussed by nonlinear least mean square fitting. The domain wall displacement and domain spin＇s contribution to permeability were separated, the result indicated that the main magnetization mechanism of Lao.67 Sro.33 Mnl_y FeyO3（y = O, 0.01） was domain wall displacement, while La0.67Sr0.33Mn1-yFeyO3（y=0,0.01,0.02,0.03） was domain spin

关 键 词：钙态矿 磁导率 畴壁位移 弛豫型 稀土 

分 类 号：O441.6[理学—电磁学]