Magnetoresistive properties of Ni-doped La_(0.7)Sr_(0.3)MnO_3 manganites

作     者：Ahmed Mohamed Ahmed Abd El-Moez Ahmed Mohamed Medhat Abdelrady Abdellateef Hassan Ahmed Abd El-Ghanny 

作者机构：Physics DepartmentFaculty of ScienceSohag University 

出 版 物：《Rare Metals》 (稀有金属（英文版）)

年 卷 期：2016年第35卷第7期

页      面：551-558页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：financially supported by Sohag University in Egypt 

主　　题：Manganites X-ray diffraction Structure Electrical resistivity Magnetoresistance 

摘      要：Lao.7Sr0.3Mnl_xNixO3 （x = 0, 0.025, 0.050 and 0.075） ceramics were prepared by the conventional solid-state reaction method. The partial substitution of Mn by Ni2＋ leads to a decrease in cell volume as well as a structural transition from the rhombohedral to the orthorhombic structure. Ni2＋ doping increases the electrical resistivity, decreases the semiconductor-metal transition temperature （Tms） and relatively enhances the room temperature magnetoresistance （MR）, especially in x = 0.025 and around Tins. With respect to conduction mechanism, the small polaron hopping （SPH） and the variable range hopping （VRH） models were used to ex- amine conduction in the semiconducting region.