Structure and Transport Properties in CMR Materials of La_((1-x)2/3)Ca_(1/3)MnO_3 with Rare Earth Vacancies  

作　　者：Li Xiaoyi Luo Guangsheng Wu Xiaoshan 

机构地区：[1]School of Material Science and Engineering, Nanchang University, Nanchang 330047, China [2]Lab of Solid Microstructures, Nanjing University, Nanjing 210093, China

出　　处：《Journal of Rare Earths》2006年第2期242-242,共1页稀土学报（英文版）

摘　　要：Samples of manganese oxides La（1-x）2/3Ca1/3MnO3（x 〈 0.10） with Lavacancy were prepared by standard solid-state reaction method. All the samples are single phase, with orthorhombic symmetry （Pnma ）, analyzed by XRD and with Rietveld Refinement. The effect of different La-site vacancies concentration on electronic transport of La（1-x）2/3Ca1/3MnO3 was investigated. The insulator-metal transition temperature （about 267 K） nearly remains unchanged with the increase of vacancy concentration, which indicates that small La-vacancy does not destroy the double exchange interaction. But the electronic resistance increases and MR value decreases with La-vacancy content x 〉 0.04. The maximum of the MR value （8 T） is about 220% at transition temperature （TMI）.Samples of manganese oxides La（1-x）2/3Ca1/3MnO3（x 〈 0.10） with Lavacancy were prepared by standard solid-state reaction method. All the samples are single phase, with orthorhombic symmetry （Pnma ）, analyzed by XRD and with Rietveld Refinement. The effect of different La-site vacancies concentration on electronic transport of La（1-x）2/3Ca1/3MnO3 was investigated. The insulator-metal transition temperature （about 267 K） nearly remains unchanged with the increase of vacancy concentration, which indicates that small La-vacancy does not destroy the double exchange interaction. But the electronic resistance increases and MR value decreases with La-vacancy content x 〉 0.04. The maximum of the MR value （8 T） is about 220% at transition temperature （TMI）.

关 键 词：La（1-x）2/3Ca1/3MnO3 La-vacancy STRUCTURE MAGNETORESISTANCE rare earths 

分 类 号：TM27[一般工业技术—材料科学与工程]