钙钛矿(La_1-_yTb_y)_(0.67)Sr_(0.33)MnO_3的超巨磁电阻效应  

THE COLOSSAL MAGNETORESISTANCE OF (La 1- y Tb y ) 2/3 Sr 1/3 MnO 3 PEROVSKITE 

作　　者：吴坚[1,2] 曹庆琪[1,2] 谷坤明[1,2] 李启亮 王亮[1,2] 张鸿才 都有为[1,2] 张世远 

机构地区：[1]南京大学物理系 [2]南京大学固体微结构物理国家重点实验室

出　　处：《物理学报》1999年第2期370-377,共8页Acta Physica Sinica

基　　金：国家科学技术委员会攀登计划;国家自然科学基金

摘　　要：采用固相反应烧结法制成了钙钛矿（Ｌａ１－ｙＴｂｙ）０．６７Ｓｒ０．３３ＭｎＯ３（ｙ＝０—１）多晶样品．研究了样品的微观结构，常温、低温下的磁性，样品的磁电阻随温度、成分的变化关系，电阻随温度变化特性等．并在ｙ＝０４０样品中，１７０Ｋ附近、最大磁化场为７Ｔ时。Abstract A series of polycrystal bulk samples of (La 1- y Tb y ) 2/3 Sr 1/3 MnO 3( x =0,0 05,0 15,0 20,0 25,0 33,0 4,0 5,0 6,1 0) have been prepared. Their microstructrues, magnetization M , resistance R as well as magnetoresistance ( MR ) have been systemically studied in the temperature range 10K≤ T ≤420K. The ferromagnetic transition temperature of the samples T C decrease with the increase y . For each sample, R have peak values at a temperature close to T C. The peak values of R increase rapidly with increasing y . At the sample ( y =0 40), a colossal magnetoresistance up to 900% has been observed on the temperature 170K.

关 键 词：钙钛矿型 锰氧化物 超巨磁电阻效应 

分 类 号：O482.5[理学—固体物理]