【摘要】 本文报道了用溶胶凝胶法并经过低温(900℃)后处理制备的具有非化学配比的La2/3Ca1/3Mn1-xO3(x=0～0.10)多晶样品的电输运和磁性质的实验研究.结果表明,随x的增加,样品呈现出明显增强的非本征磁电阻效应,同时其本征磁电阻效应减弱.实验还观察到样品的颗粒尺寸随x的增加而减小的现象.基于样品的结构特征,本文讨论了其独特输运性能的形成原因.更多还原

【Abstract】 Magnetic and electrical transport properties are experimentally studied for non-stoichiometric Mn based polycrystalline samples of nominal composition La_ 2/3Ca_ 1/3Mn_ 1-xO_ 3 (x=0~0.10), which are prepared by the sol-gel method followed sintering treatment at 900℃. The results show that with the increase of x, extrinsic magnetoresistance enhances while intrinsic magnetoresistance decreases. It is also observed that the average grain size of the samples decreases with x. Based on the structural investigation, the experimental observations are discussed.更多还原