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中文摘要：
采用传统固相法制备钙钛矿锰氧化物（La0.9Eu0.1）4/3Sr5/3Mn2O7多晶样品。通过XRD表明,样品（La0.9Eu0.1）4/3Sr5/3Mn2O7呈现单相性良好;通过对磁化强度随温度变化（M-T）、磁化强度在不同温度下随磁场变化曲线（M-H）和电子自旋共振ESR谱线表明,随着温度的升高,样品先后经历了三维长程铁磁有序转变点（TC^3D≈75 K）和二维短程铁磁有序转变点（TC^2D≈227 K）,在TC^3D与TC^2D之间,系统处于铁磁与顺磁混合态;当温度达到360 K系统进入纯顺磁态,另外样品在低温区（TC^3D以下）出现类团簇自旋玻璃特征。通过磁电阻随温度变化的ρ-T曲线,在T≈84 K附近,样品出现最大磁电阻。而且通过对（La0.9Eu0.1）4/3Sr5/3Mn2O7的ρ-T曲线拟合,得到样品在高温区域的导电方式为热激活模型。
英文摘要：
Samples（La0.9Eu0.1）4/3Sr5/3Mn2O7were prepared by solid state reaction method. X- ray diffraction patterns indicated the sample shows no any asymmetry and no any trace of secondary phase. Through the magnetization curve with the temperature（ M-T） and magnetization curve with magnetic field under different temperatures（ M-H） and the ESR spectrum detection,it is found that,with temperature increasing,all the samples undergo a complex magnetic transition. They transform from the two-dimensional short-range ferromagnetic order at TC^2D≈ 227 K and enter the three-dimensional long-range ferromagnetic state at TC^3D≈75 K. Between TC^3D and TC^2D,both paramagnetic phase and antimagnetic phase exist. When T = 360 K,paramagnetic phase appears in the sample. Besides,the sample reflects a characteristic of cluster spin glass at low temperature range which is under TC^3D. Through electrical resistivity curve with the temperature ρ-T,the sample shows the max magnetization electrical resistivity when metal-insulator transition temperature T ≈84 K. It can be seen from the fitted ρ-T curves of（La0.9Eu0.1）4/3Sr5/3Mn2O7that the electron conducting mechanism in high temperature range is in accordance with thermal activated model.
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