La_(0.75)Na_(0.25)MnO_3外延膜的制备及电流诱导效应  

Preparation and Current-induced effect of epitaxial film La_(0.75)Na_(0.25)MnO_3

作　　者：渊小春[1] 韩立安[1] 张秀霞[2] 

机构地区：[1]西安科技大学理学院,陕西西安710054 [2]西安交通大学电信工程学院,陕西西安710049

出　　处：《陕西师范大学学报（自然科学版）》2010年第4期32-35,共4页Journal of Shaanxi Normal University：Natural Science Edition

基　　金：国家自然科学基金资助项目(60844006);陕西省自然科学基金资助项目(2009JQ1005)

摘　　要：通过射频磁控溅射,在单晶LaAl O3(100)衬底上生长了膜厚为120 nm的La0.75Na0.25MnO3外延膜.应用X射线衍射仪、直流四探针法对其结构及电流诱导效应进行了系统研究.X射线结果表明:薄膜具有赝立方钙钛矿结构,为(100)取向外延膜.电阻率与温度关系表明La0.75Na0.25MnO3薄膜在275 K附近发生金属与绝缘体转变.电流在0.5～4 mA范围内,薄膜的峰值电阻率随电流增大而减小,在4 mA下获得了15.9%的峰值电阻率变化,并应用相分离理论给出了合理的解释.Using the magnetron sputtering method,La0.75Na0.25MnO3 film with the thickness of 120 nm was epitaxially grown on LaAlO3（100） single-crystal substrate.The film was characterized by the X ray diffraction and the Dc four probe method.The X-ray diffraction patterns show that the thin film is a pseudo-cubic perovskite type structure with the epitaxial direction of（100）.The resistivity-temperature curve shows that the film undergoes metal-insulator transition at 275 K.The peak resistivity decreases with the increment of the currents between 0.5～4mA and that of the 15.9% is obtained at 4mA.The results are reasonably explained by phase-separation theory.

关 键 词：La0.75Na0.25MnO3外延膜 电流诱导效应 相分离理论 

分 类 号：O484.1[理学—固体物理]