Nd0．67Pb0．33MnO3薄膜的磁性及输运特性  

Magnetic properties and transport properties of Nd_(0.67)Pb_(0.33)MnO_3 film

作　　者：韩立安[1] 廖少俊[1] 陈长乐[2] 

机构地区：[1]西安科技大学基础部,陕西西安710054 [2]西北工业大学理学院,陕西西安710072

出　　处：《功能材料》2008年第8期1286-1288,共3页Journal of Functional Materials

基　　金：国家自然科学基金(50331040，60171034);西安科技大学培育基金(200737)

摘　　要：通过射频磁控溅射法在单晶LaAlO_3(100)衬底上成功的生长了Nd_(0.67)Pb_(0.33)MnO_3薄膜。用X射线衍射仪、超导量子干涉仪、直流四探针法对其结构及磁电特性进行了研究。结果表明,薄膜为赝立方钙钛矿结构,晶胞参数为a=3.846nm。居里温度为158K。在居里温度附近,发生铁磁-顺磁转变,导电特性由金属特征向半导体特征过渡。此材料呈现出一种典型的自旋玻璃特性,是由于应力造成的。磁电阻在居里点附近达到极大值,当H=1.0T时,磁电阻的极大值为28.5%。输运性质表明,T<T_(MI)时,电阻率满足公式:ρ(T)=ρ_0+ρ_1T^2+ρ_2T^5此输运机制是由电子散射造成的;当T>T_(MI)时,符合小极化子模型,输运机制是由于小极化子近邻跃迁引起的。Using magnetron sputtering method, Nd0. 67 Pb0. 33 MnO3 thin film was grown on （100） LaAlO3 singlecrystal substrates. The thin film was investigated by X-ray diffraction, superconducting quantum interference device and De four probed method. The results show that the thin film have a pseudo-cubic perovskite structure with the cell parameter α= 3.846nm. The Curie temperature is 158K. Near the Curie temperature, the magnetic property shows a transition from ferromagnetic to paramagnetic. The electrical property indicates a transition from metal to semiconductor. Nd0.67 Pb0.33 MnO3 thin film exhibit a characteristic spin glass state from zero-field cooled and field cooled magnetization curve, which is due to strain effects. The thin film has quite a distinctive magnetoresistance effect which is 28.5% near the Curie temperature when the magnetic field is 1T. Transport properties indicate that the resistivity satisfy model, ρ（T）=ρ0＋ρ1 T^2 ＋ρ2 T^5 when the temperature is below TMI due to electron-electron scattering, the resistivity satisfy polarons model when the temperature is above TMI owing to the existence of the small polarons nearest hopping.

关 键 词：Nd0.67Pb0.33MnO3薄膜 磁性 输运特性 小极化子 

分 类 号：O482.5[理学—固体物理]