采用空气中固相反应烧结法制备了一系列钙钛矿结构的(La1-xREx)2/3Sr1/3MnO3(RE=Y,Sm,Eu,Tb;x=0.1~0.5)稀土锰氧化物多晶样品.X射线衍射(XRD)分析表明掺杂RE部分替代La以后,样品的晶体结构为正交结构,空间群为Pbmm.在室温(300K)和液氮温度(77K)下分别测试了样品的磁性质,发现磁性质的改变与RE的掺入量以及RE的离子半径有关.在掺Tb的样品中明显存在巨磁电阻效应,磁场为2 T,温度为300和77 K分别测得(La0.6Tb0.4)2/3Sr1/3MnO3和(La0.7Tb0.3)2/3Sr1/3MnO3的磁电阻(MR)为80%和85%.随着Tb掺杂量的增加,在不同的磁场下,样品电阻-温度关系曲线的峰均向高温方向移动.
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