La_(0.3)Sr_(0.7)FeO_3薄膜的输运和光诱导特性研究  

Transport and Photoinduced Properties of La_(0.3)Sr_(0.7)FeO_3 Thin Films

作　　者：金克新[1] 赵省贵[2] 谭兴毅[1] 陈长乐[1] 

机构地区：[1]西北工业大学,陕西西安710072 [2]西安科技大学,陕西西安710054

出　　处：《稀有金属材料与工程》2010年第1期76-79,共4页Rare Metal Materials and Engineering

基　　金：国家自然科学基金重点项目(50331040);国家自然基金项目(50702046);西北工业大学翱翔之星项目资助

摘　　要：采用射频(RF)磁控溅射法制备稀土掺杂铁氧化物La0.3Sr0.7FeO3(LSFO)薄膜。电阻-温度关系表明,薄膜在测量温度范围内呈现半导体导电特性,其主要源于Fe3+和Fe5+离子的电荷有序排列,同时薄膜在250K时发生电荷有序态转变。激光作用诱导薄膜电阻减小,且光致电阻相对变化在190K时取得极大值为56.3%。利用变程跳跃模型对电阻温度曲线进行分析讨论,表明激光作用的内在机制是激光辐照诱导电子退局域化。La0.3Sr0.7FeO3 （LSFO） thin films were prepared by RF magnetron sputtering method. The resistance-temperature relation shows that the film favors the semiconductive conduction in the testing temperature range, which arises from the charge ordering of Fe3＋ and Fe5＋ ions. The charge ordering transition happened at T=250 K. The laser irradiation induces a decrease of the resistance of the film and the maximum relative change in the photoinduced resistance is about 56.3% at T=190 K. The analysis of the resistance-temperature relation using the variable range hoping （VRH） model shows that the intrinsic mechanism of the laser irradiation is the delocalization of the electrons.

关 键 词：输运特性 光诱导特性 Jahn—Teller效应 

分 类 号：TB383.2[一般工业技术—材料科学与工程]