Mn位Cr掺杂对亚锰酸盐La0.7Ca0.3MnO3低场磁电阻影响  

Effect of Cr Dopingin Mn Site on Low Field Magnetoresistance of Manganite La0.7Ca0.3MnO3

作　　者：张光宇 刘琳婧 ZHANG Guang-yu;LIU Lin-jing(School of Applied Sciences,Harbin University of Science and Technology,Harbin 150080,China)

机构地区：[1]哈尔滨理工大学理学院

出　　处：《哈尔滨理工大学学报》2019年第3期130-133,共4页Journal of Harbin University of Science and Technology

基　　金：黑龙江省自然科学基金(F200831);黑龙江省大学生创新创业训练计划项目(201510214050)

摘　　要：为了研究钙钛矿亚锰酸盐在较低磁场下的磁电阻效应,采用固相反应法制备了亚锰酸盐多晶样品La0.7Ca0.3Mn1-xCrxO3(x=0,0.1),测量了两个样品在未加磁场和加0.25 T磁场的电阻-温度曲线及磁电阻-温度曲线,分析了Mn位Cr掺杂对样品低场磁电阻效应的影响。实验结果表明,随着Cr掺杂量从x=0增加到x=0.1,样品的金属-绝缘体转变温度逐渐向低温推移,磁电阻峰值温度由TP≈220 K下降到TP≈190 K。在0.25 T磁场下,样品在液氮温区具有较明显的磁电阻效应。In order to study the magnetoresistance effect of perovskite manganite in low magnetic fields,manganite polycrystalline samples La 0.7 Ca 0.3 Mn 1-x Cr x O 3(x=0,0.1)were prepared by solid-state reaction technique.Resistance-temperature curves and magnetoresistance-temperature curves of the two samples were measured in zero magnetic field and 0.25 T magnetic field.Influence of different substitution of Cr for Mn on low field magnetoresistance effects of the samples was analyzed.Experimental results showed that the metal-insulator transition temperature of the samples gradually moved to lower temperature and the magnetoresistance peak temperature of the samples decreased from T P≈220 K to T P≈190 K with the increase of Cr doping from x=0 to x=0.1.The samples showed large magnetoresistance over liquid nitrogen temperature range in 0.25 T magnetic field.

关 键 词：亚锰酸盐 固相反应 双交换 低场磁电阻 

分 类 号：O482[理学—固体物理]