Title :
Effect of process conditions and NiO on magnetoresistance of La-(Ca,Ba)-Mn-O composites
Author :
Shuiyuan Chen ; Xu, Yan ; Ye, Qingying ; Zhigao Chen ; Huang, Zhigao ; Wang, Dunhui ; Du, Youwei
Author_Institution :
Dept. of Phys., Nanjing Univ., Nanjing
Abstract :
La2/3(Ca0.6Ba0.4)1/3MnO3/XNiO heterogenous composites have been synthesized by modified sol-gel method. Resistivity versus temperature in difference magnetic fields for the samples, as well as magnetoresistance (MR) versus magnetic in room temperature, have been measured. It is indicated that the addition of NiO results to the increase in resistivity and the weakeness in magnetization. Enhanced MR has been obtained in NiO-doped composites. The temperature dependence of magenetoresistance for NiO-doped composites in low magnetic field may be explained by the model of spin-polarized tunneling. The vary trend of MR in MR-T curve is similar to the result obtained by Monte Carlo simulation. MR in high magnetic field may be explained by spin polarization inside ferromagnetic grains.
Keywords :
Monte Carlo methods; barium compounds; calcium compounds; colossal magnetoresistance; lanthanum compounds; magnetic tunnelling; magnetisation; nanocomposites; nanoparticles; nickel compounds; spin polarised transport; La0.67(Ca0.6Ba0.4)0.33MnO3:NiO; Monte Carlo simulation; colossal magnetoresistance; ferromagnetic grains; heterogenous composites; magnetization; modified sol-gel method; process conditions effect; resistivity; room temperature; spin-polarized tunneling; temperature 293 K to 298 K; Magnetoresistance; Nanoelectronics;
Conference_Titel :
Nanoelectronics Conference, 2008. INEC 2008. 2nd IEEE International
Conference_Location :
Shanghai
Print_ISBN :
978-1-4244-1572-4
Electronic_ISBN :
978-1-4244-1573-1
DOI :
10.1109/INEC.2008.4585665
