La_(0.67)Ca_(0.33)MnO_3和La_(0.67)Ba_(0.33)MnO_3中Dy的置换作用  

Substituting effects of Dy in La0.67Ca0.33MnO3 and La0.67Ba0.33MnO3

作　　者：刘宜华[1] 张汝贞[1] 王成建[1] 黄宝歆[1] 代由勇[1] 原晓波[1] 梅良模[1] 

机构地区：[1]山东大学物理学院和晶体材料国家重点实验室,山东济南250100

出　　处：《功能材料》2003年第2期148-150,共3页Journal of Functional Materials

基　　金：国家重点基础研究专项资助项目(G19980613010)

摘　　要：在La0.677 Ca0.33 MnO3和La0.67 Ba0.33 MnO3中用Dy对La进行了置换研究,结果发现,随掺Dy量的增加,两类材料的居里温度和金属-绝缘体相变温度单调下降,峰值电阻率单调增加。在Ca系样品中,掺入13％的Dy后,在5T的磁场下,最大磁电阻比达到7900％。在Ba系样品中,掺Dy对磁电阻的影响要小得多。掺Dy对材料性质的影响可以用晶格效应来解释,但晶格效应产生的作用与碱土离子的品种有明显关系。Substituting effects of Dy for La in La0.67Ca0.33MnO3 and La0.67Ba0.33MnO3 have been studied. The results indicate that with increasing Dy content, the Curie temperature and metal-insulator transition temperature for these two series of samples decrease monotonically, the peak resistivity increases monotonically. When 13% Dy was doped into the Ca-based samples, the maximum magnetoresistant ratio reached to 7900% in a 5T magnetic field. While in the Ba-based samples, the influence of doping Dy on the magnetorasistance is much smaller. The effects of doping Dy on the properties of materials can be explained in terms of lattice effect. However, the lattice effect was obviously dependent on the species of alkaline-earth ions.

关 键 词：稀土 掺杂 锰氧化物 庞磁电阻 晶格效应 X射线衍射 

分 类 号：TM27[一般工业技术—材料科学与工程]