用外延应力来调控不同衬底上的La0.7Sr0.3MnO3薄膜的结构性质和磁电阻性质  

Tuning Structural and Magnetoresistance Properties of La0.7Sr0.3MnO3 Thin Films by Epitaxial Strains

作　　者：姚盼盼 董洪光[2] 罗毅 郭海中 Panpan Yao;Hongguang Dong;Yi Luo;Haizhong Guo(School of Physical Engineering,Zhengzhou University,Zhengzhou Henan;Higher Education Press,Beijing)

机构地区：[1]郑州大学物理工程学院,河南郑州 [2]高等教育出版社,北京

出　　处：《应用物理》2018年第8期353-361,共9页Applied Physics

摘　　要：在这个工作中,我们研究了利用脉冲激光沉积技术在不同衬底上外延生长出La0.7Sr0.3MnO3外延薄膜的结构、输运、磁性、及磁电阻性质。用X射线衍射技术测量的结果表明在不同衬底上制备的La0.7Sr0.3MnO3薄膜是外延生长并且是单相的。La0.7Sr0.3MnO3薄膜的晶格常数c随由于薄膜与衬底的晶格失配引起的外延应力的变化而变化。磁性性质和电输运性质的测量结果分别表明不同衬底上的La0.7Sr0.3MnO3薄膜具有不同的顺磁–铁磁转变温度(居里温度TC)和金属–绝缘体转变温度(TR)。此外,不同衬底上La0.7Sr0.3MnO3薄膜的电阻率ρ(T)和磁电阻也随着外延应力而变化。我们的实验说明了外延应力是调控外延薄膜物性很有力的工具。Structural, transport, magnetic, and magnetoresistance properties of the epitaxial La0.7Sr0.3MnO3 thin films on different substrates grown by pulsed laser deposition were investigated. The results of X-ray diffraction show that all the La0.7Sr0.3MnO3 thin films are epitaxial growth and at single phase, and the lattice parameter c changes with the epitaxial strain due to the lattice mismatch between the thin film and the different substrates. The results of the magnetization and the electrical transport measurements indicate that the La0.7Sr0.3MnO3 thin films grown on different substrates have different Curie temperature TC and metal-to-insulator transition temperature TR, respectively.Moreover, the resistivity ρ(T) and corresponding magnetoresistance of the La0.7Sr0.3MnO3 thin films change with the epitaxial strain. Our findings show that the epitaxial strain is a powerful tool for tuning the properties of the epitaxial thin films.

关 键 词：La0.7Sr0.3MnO3薄膜 脉冲激光沉积 外延应力 磁电阻 

分 类 号：O48[理学—固体物理]