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系统研究了 (La1 -xYx) 2 3Ca1 3MnO3(0 0≤x≤ 0 3)体系的结构和输运行为 .结果表明 ,实验样品具有很好的单相结构 ,随Y掺杂浓度的增加 ,金属—绝缘体 (M—I)转变温度TMI向低温区移动 ,对应的峰值电阻率 ρp 升高 ,对x =0 3样品 ,较未替代样品 (x=0 0 )增幅达 8个数量级 .在外加磁场下 ,材料表现出很强的磁电阻效应 .同时 ,从实验结果出发 ,直接给出了输运特性与晶体结构之间的关联 ,并从双交换模型和可变程跃迁理论出发 ,对实验结果进行了初步讨论 .
The structure and transport behavior of (La1-xYx) 2 3Ca1 3MnO3 (0 0≤x≤0 3) system were studied systematically.The experimental results show that the experimental sample has a good single-phase structure. With the increase of Y doping concentration, - The transition temperature TMI of the insulator (M-I) moves to the low temperature region, and the corresponding peak resistivity ρp increases. For the sample with x = 0 3, the amplitude increases by 8 orders of magnitude compared with the un-substituted sample , The material shows a strong magnetoresistance effect.At the same time, from the experimental results, the relationship between the transport properties and the crystal structure is directly given, and from the double exchange model and the variable transition theory, the experimental results Conducted a preliminary discussion.