Magnetoresistance enhancement and temperature stability of magnetoresistance in La_(1-x)(Sr_(1-y)Na_y)_xMnO_3  

作　　者：Wang, Guiying  Yan, Guoqing  Yang, Jie  Wang, Wenqi  Tang, Yonggang  Song, Qixiang  Zhang, Mingyu  Peng, Zhensheng 

机构地区：[1]Anhui Key Laboratory of Spintronic and Nanometric Materials(Cultivating Base),Suzhou 234000,China [2]School of Mechanical and Electronic Engineering,Suzhou University,Suzhou 234000,China [3]Hefei National Laboratory for Physical Sciences at the Microscale,University of Science and Technology of China,Hefei 230026,China

出　　处：《Rare Metals》2012年第4期387-391,共5页稀有金属（英文版）

基　　金：supported by the National Natural Foundation of China (No. 19934003);the Natural Science Research Key Program of Anhui Educational Committee (No. KJ2011A259);the Cultivating Base of Anhui Key Laboratory of Spintronics and Nano-materials Research Program(No. 2010YKF01;No. 2010YKF04);the Professors’ and Doctors’ Research Startup Foundation of Suzhou University (Nos. 2011jb01 and 2011jb02)

摘　　要：A series of the samples La_(1-x)(Sr_(1-y)Na_y)_xMnO_3(y=0.0,0.2,0.4,0.6,0.8,1.0) were prepared by the solid-state reaction method.Magnetoresistance enhancement and temperature stability of magnetoresistance in the system La_(1-x)(Sr_(1-y)Na_y)_xMnO_3 with unchanged Mn^(3+)/Mn^(4+) ratio through the doping of both monovalent and divalent elements at A site were studied through the measurements of X-ray diffraction(XRD) patterns,resistivity-temperature(ρ-T) curves and magnetoresistance-temperature(MR-T) curves.The results indicate that with the increase of Na doping amount,the peak value of MR increases,and it increases from 12.4% for y=0.2 to 50.6% for y=1.0 in the magnetic field B=0.8 T;ρ-T curves exhibit the double-peak phenomenon,which comes from the competition between the resistivity of surface phase and that of body phase;for the sample of y=0.8,MR increases slowly from 8.3% to 9.4% in the temperature range from 259 to 179 K,and MR is so stable in such a wide temperature range,which provides reference for the research on the temperature stability of MR.

关 键 词：magnetoresistance enhancement temperature stability perovskite manganite 

分 类 号：O611.3[理学—无机化学]