La-Gd-Ca-Mn-O的磁性、电性和磁电阻效应

材料科学与工程学报, 2001, 19(1): 17-5. doi: 10.3969/j.issn.1673-2812.2001.01.004

La-Gd-Ca-Mn-O的磁性、电性和磁电阻效应

刘宜华 ^1, , 岳龙强 ^2, , 徐丽 ^3, , 黄佶 ^4, , 季刚 ^5, , 王成建 ^6, , 张汝贞 ^7, , 胡季帆 ^8, , 梅良膜 ^9,

1.山东大学物理系,

2.山东大学物理系,

3.山东大学实验中心,

4.山东大学实验中心,

5.山东大学物理系,

6.山东大学物理系,

7.山东大学物理系,

8.山东大学物理系,

9.山东大学物理系,

基金项目: 国家自然科学基金(59772040) 国家重点基础研究发展计划(973计划)(G19980613)

关键词：钙钛矿结构 , 稀土掺杂锰氧化物 , 超大磁电阻(CMR)

Magnetic and Electric Properties and Magnetoresistive effects of La-Gd-Ca-Mn-O

在La0.67Ca0.33MnO3中进行了掺Gd研究，结果发现，经1400℃烧结的样品，获得了最佳的磁电阻效应。随掺Gd量增加，材料的相变温度逐渐下降，对应的峰值电阻率大幅度增加，居里温度逐渐下降，磁电阻比明显提高。掺入11%的Gd后，可以使磁电阻比提高一个数量级。这些变化可以用晶格效应来解释。

The doping effects of Gd in La0.67Ca 0.33MnO3 were studied. It was found that the optimum magnetoresistive e ffect was obtained by the sample sintered at 1400℃. With increasing the doping amount of Gd, the transition temperature of the samples decreased monotonically, the corresponding peak resistivity increased dramatically, the Curie temperatur e decreased monotonically, the magnetoresistance ratio increased significantly. The substitution of 0.11% Gd for La improved the magnetoresistance ratio by an order of magnitude. These changes can be explained by the lattice effects.

参考文献

[1]	A J Millis;P B.Littlewood;B.I.Shraiman .Double exchange alone does not explain the resistivity of La1-xSrxMnO3[J].Physical Review Letters,1995,74:5144.
[2]	M R Ibarra;P A.Algarabel;C.Marquina;J Blasco and J.Garcia .Large magnetovolume effect in yttrium doped La-Ca-Mn-O perovskite[J].Physical Review Letters,1995,75:3541.
[3]	D N Argyriou;J F.Mitchell;C.D.Potter;S D.Bader R.Kleb and J.D.Jorgensen .Unconventional magetostriction in layered La1.2Sr1.8Mn2O7:evidence for spin-lattice couplng above TC[J].Physical Review B,1997,55:R11965.
[4]	J -S Zhou;J B.Goodenough;J.F.Mitchell .Presure-induced phase segregation in single-crystal La2-2xSr1+2xMn2O7(x=0.32)[J].Physical Review B,2000(61):R9217.
[5]	S. Jin;H. M. O'Bryan;T. H. Tiefel;M. McCormack;W. W. Rhodes .Large magnetoresistance in polycrystalline La-Y-Ca-Mn-O[J].Applied physics letters,1995(3):382-384.
[6]	H Y Hwang;S -W.Cheong;P.G.Radaelli;M Marezio and B.Batlogg .lattice effect on the magnetoresistance in doped LaMnO3[J].Physical Review Letters,1995,75:914.
[7]	S Jin;M McCormack;T.H.Tiefel;R Ramesh .Colossal magnetoresistance in La-Ca-Mn-O ferromagnetic thin films[J].Journal of Applied Physics,1994,76:6929.

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