无机材料学报2016，Vol.31Issue(3)：274-278,5.DOI:10.15541/jim20150397
La0.7Ca0.3-xSrxMnO3薄膜的电输运特性研究
Electrical Transport Properties in La0.7Ca0.3-xSrxMnO3 Thin Films
摘要
Abstract
The influence of the chemical composition on the structure, magnetic and electrical transport properties of La0.7Ca0.3-xSrxMnO3 (LCSMO,x≤0.05) thin films was systematically studied. LCSMO thin films were prepared by Sol-Gel method. XRD results show that all the films have typical perovskite structure. With increase of Sr dop-ing concentration, both Curie temperatureTC and metal-insulator transition temperatureTMI of LCSMO thin films increase monotonously. When Sr doping concentrationx≤0.05, with increase of temperature, absolute value of MR decreases first, then increases to a maximum value aroundTMI, and finally decreases, which indicates that the dis-order coming from phase separation aroundTMI contributes greatly to MR. The field dependence of MR values at certain temperature can be classified into two kinds. When the temperature is much lower thanTMI, dual gradient of MR with the magnetic field is shown. The tunneling effect on the grain boundaries plays a dominant part in the low magnetic field, and this effect is particularly sensitive to the magnetic field; the suppression of spin fluctuations by magnetic field is the main reason in the high magnetic field range. When the temperature is higher thanTMI, MR of LCSMO thin films changes almost linearly with the magnetic field which is mainly due to suppression of spin fluc-tuations by magnetic field.关键词
锰氧化物/溶胶–凝胶法/电输运特性Key words
manganese oxides/Sol-Gel method/transport properties分类
化学化工引用本文复制引用
张媛媛,唐晓东,陈莹,王根水,董显林..La0.7Ca0.3-xSrxMnO3薄膜的电输运特性研究[J].无机材料学报,2016,31(3):274-278,5.基金项目
国家自然科学基金(51302084, 11304097, 61176011, 61376129, 11374098) National Natural Science Foundation of China (51302084, 11304097, 61176011, 61376129, 11374098) （51302084, 11304097, 61176011, 61376129, 11374098）
