Giant Low-Field Magnetoresistance in Polycrystalline La2/3Ca1/3Mn1-xCuxO3 Sintered at 1100 ℃

稀土学报(英文版), 2004, 22(3): 414-417.

杨应平 ^1, , 袁松柳 ^2, , 刘洁 ^3, , 张国庆 ^4, , 夏正才 ^5,

1.Department of Physics,Huazhong University of Science and Technology, Wuhan 430074, China;Department of Physics, Wuhan University of Technology, Wuhan 430070, China

2.Department of Physics,Huazhong University of Science and Technology, Wuhan 430074, China;Department of Physics, Wuhan University of Technology, Wuhan 430070, China

3.Department of Physics,Huazhong University of Science and Technology, Wuhan 430074, China

4.Department of Physics,Huazhong University of Science and Technology, Wuhan 430074, China

5.Department of Physics,Huazhong University of Science and Technology, Wuhan 430074, China

基金项目: 国家自然科学基金(10174022)

Giant Low-Field Magnetoresistance in Polycrystalline La2/3Ca1/3Mn1-xCuxO3 Sintered at 1100 ℃

Keywords： condensed matter physics

The La2/3Ca1/3Mn1-xCuxO3 (0≤x＜6%) samples were prepared by sol-gel method. Transport properties, conductive mechanism and low-field magnetoresistance (MR0) were investigated. It is found that conductive mechanism is described by Mott′s variable-range hopping and the MR0 near the insulator-metal transition temperature (Tp) increases from 2% to 80% with x from 0 to 4% for a low field of 0.3 T. The experiment also shows that the intergrain magnetoresistance is largely improved. The results indicate that a proper amount of Cu doping can substantially improve magnetoresistance effects.

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Giant Low-Field Magnetoresistance in Polycrystalline La2/3Ca1/3Mn1-xCuxO3 Sintered at 1100 ℃

参考文献