中文摘要：

采用软化学方法制备了不同粒径的La0.9Sr0.1MnO3和软磁材料γ-Fe2O3，并将两者按不同比例进行复合，分别用扫描电子显微镜和X射线技术观察了样品的形貌特征和相结构，发现掺杂后的复合体系的电阻率要远大于未掺杂样品的电阻率。掺入γ-Fe2O3后，样品表现出异常磁电阻效应，即加外磁场后样品的电阻率明显大于禾加磁场时样品的电阻率。同时，掺杂样品磁电阻的磁场灵敏度显著提高，在室温附近观察到了磁电阻极大值。

英文摘要：

Perovskite manganite La0.9Sr0.1MnO3 and soft-ferrite γ-Fe2O3 were prepared by using sol-gel method,and γ-Fe2O3 was doped in La0.9Sr0.1MnO3 With different ratio. The morphology and phase structure were investigated by using SEM and XRD respectively. The resistance of the composition is larger than the sample La0.9Sr0.1MnO3 There is an exceptional magnetoresistance effect was founded after γ-Fe2O3 was doped in,that is the resistance of the sample with field higher than the one without field. At the same time, there is an obvious improve of the field susceptivity of the sample,and a magnetoresistance maximum was founded at the near of room temperature.