用固相反应法制备了(1 -x)La0.6Dy0.1Sr0.3MnO3/0.5x( Sb2 O3)系列样品,通过电阻率-温度(ρ-T)曲线以及ρ-T拟合曲线,研究了样品的电输运性质,电输运机制及低场磁电阻效应.结果表明:所有样品在高温区表现为绝缘体导电,在低温区表现为金属导电,产生绝缘体-金属相变;在金属导电区主要是单磁子散射起作用,可以用公式ρ=ρ0+AT拟合;所有样品在整个温区随温度降低MR持续增大,表现出低场磁电阻特征,复合样品的磁电阻(MR)与纯的La0.6Dy0.1Sr0.3 MnO3的MR相比,在低温区减小,在高温区增大,对x=0.15的样品在高温区的MR大幅度提高,当B=0.2 T,T=300 K时,MR达7.79%,比纯La0.6Dy0.1 Sr0.3 MnO3的MR增大2.6倍,有利于MR的实际应用.
参考文献
[1] | Ziesem .Extrinsic magneto transport phenornena in ferromagnetic oxides[J].Reports on Progress in Physics,2005,65:143. |
[2] | Kou Zhi-Qi,Di Nai-Li,Ma Xiao,Li Qing-An,Cheng Zhao-Hua.Enhancement of "intrinsic" magnetoresistance ratio and activation energy of La0.67Ca0.33MnO3 single crystals by Fe doping[J].中国物理(英文版),2005(08):1653-1656. |
[3] | Peng Z S;Wang G Y;Lin P;Niu X F .Enhancement of roomtemperature magnetuvesistance in La0.5 Sm0.2 Sr0.3 MnO3 /(Ag2O)x/2[J].Rare Metals,2010,29(01):45. |
[4] | SONG Qixiang,NIU Xiaofei,WANG Guiying,TANG Yonggang,CAI Zhirang,PENG Zhensheng.Enhancement of room-temperature magnetoresistance in La_(0.6)Dy_(0.1)Sr_(0.3)MnO_3/Ag_x[J].稀有金属(英文版),2010(02):126-131. |
[5] | Balcells L;Martinez B;Sandiumenge F .Magnetotrabport properties of a single grain boundary in a bulk La-Ca-Mn-O material J.Fontcuberta[J].Journal of Magnetism and Magnetic Materials,2011,211:193. |
[6] | Hueso L E;Riras J;Rivadulla F;lopez-Quintela M A .The exceptional magnetore-sistance effect of the composition system La0.9Sr0.1MnO3/Fe2O3[J].Journal of Applied Physics,2001,89:1746. |
[7] | Jin S;Tiefel T H;Mccormack M .Thousandfold change in resistivitg in magnetoresistive La-Ca-Mn-O films[J].Science,1994,264:413. |
[8] | Hwang H Y;Cheong S W;Ong N P;Batlogg .Spin-polarized intergrain tunneling in La2/3 Sry3 MnO3[J].Physical Review Letters,1996,77:2041. |
[9] | Wang X L;Dou S X;Liu H K;Ionescu M,Zeimetz B .Large Low-field magnetoresistance over a wide temperature range induced by weak-link grain boundaries in Le0.7 Ca0.3.MnO3[J].Physical Review Letters,1998,73(03):396. |
[10] | 张炯,魏立国,张蕾,李定国,熊永红,熊曹水.Ag掺杂对La0.7Ca0.2Sr0.1MnO3室温磁电阻效应的增强[J].低温物理学报,2007(02):86-89. |
[11] | 王桂英,彭振生,唐永刚,刘鹏,牛晓飞.La_(0.5)Sm_(0.2)Sr_(0.3)MnO_3/Ag_x二相复合体的结构及磁电阻[J].稀有金属,2010(02):210-214. |
[12] | 袁力,缪菊红,王永强,刘莉,袁松柳.(1-x)La2/3Ca1/3MnO3/xSb2O5复合体系的电子输运和磁电阻行为[J].无机材料学报,2007(02):319-322. |
[13] | Zjang N;Ding W;Zhong W;Xing D,Du Y .Tunnel-typegiant magnetoresistance in the granul perovskite La0.85Sr0.15MnO3[J].Physical Review B,1997,56:8138. |
[14] | Okuda T.;Tomioka Y.;Kimura T.;Taguchi Y.;Tokura Y.;Asamitsu A. .Critical behavior of the metal-insulator transition in La1-xSrxMnO3[J].Physical review letters,1998(15):3203-3206. |
[15] | Deteresa JM.;Blasco J.;Garcia J.;Marquina C.;Algarabel PA. Arnold Z.;Kamenev K.;Ritter C.;Vonhelmolt R.;Ibarra MR. .SPONTANEOUS BEHAVIOR AND MAGNETIC FIELD AND PRESSURE EFFECTS ON LA2/3CA1/3MNO3 PEROVSKITE[J].Physical Review.B.Condensed Matter,1996(2):1187-1193. |
[16] | Mandal P.;Haupt L.;Poddar A.;von Helmolt R.;Jansen AGM. Wyder P.;Barner K. .High-field magnetotransport properties of La2/3Sr1/3MnO3 and Nd2/3Sr1/3MnO3 systems[J].Physical Review.B.Condensed Matter,1998(17):10256-10259. |
[17] | Fath M;Freisem S;Menovsky A A;Tomioka Y Aarts J Mydosh J A .Spatially inhomogeneous metal-insulator transition in doped manganites[J].Science,1999,285:1540. |
[18] | Zhang N.;Zhong W.;Xing DY.;Du YW.;Ding WP. .TUNNEL-TYPE GIANT MAGNETORESISTANCE IN THE GRANULAR PEROVSKITE LA0.85SR0.15MNO3[J].Physical Review.B.Condensed Matter,1997(13):8138-8142. |
[19] | Neeraj Khare;U. P. Moharil;A. K. Gupta;A. K. Raychaudhuri;S. P. Pai;R. Pinto .Temperature dependence of magnetoresistance and nonlinear conductance of the bicrystal grain boundary in epitaxial La_(0.67)Ba_(0.33)MnO_(3) thin films[J].Applied physics letters,2002(2):325-327. |
[20] | Sánchez R D;Rivas J;Vázquez-Vázquez C;López-Quintela A,Causa M T,Tovar M,Oseroff S .Giant magnetoresistance in fine particle ofLa0.67Ca0.33MnO3[J].Applied Physics Letters,1996,68(01):134. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%