Study of Temperature Stability of the Magnetoresistance and Transport Properties in La_(0.6)Sr_(0.15)Na_((0.1)□0.15)MnO_3 with the Addition of Ag

摘要

A series of bulk polycrystalline samples of La_(0.6)Sr_(0.15)Na_((0.1)□0.15)MnO_3 represents vacancy)with Ag addition were prepared by conventional Sol-gel reaction processing in air. The mol proportion between La_(0.6)Sr_(0.15)Na_((0.1)□0.15)MnO_3 and Ag is l:x (x=0.00,0.016,0.04,0.1). This article focuses on the impact of Ag doping on the parent structure, magnetic properties and magnetoresistance. We have gotten the following experimental results: X-ray diffraction patterns show that a weak Ag phase appears when x≥ 0.04 ;The Curie temperature of the doped samples is higher than that of the matrix sample and it reduces as x increases. The resistivity of the doped samples is bigger than that of the parent sample in zero field and it increases as x increases.In a quite wide temperature range (207K-286K), MR maintains the value of 5.08% (+0.20%) when x=0.04. So the CMR temperature stability has been improved.