Electric transport mechanism and magnetoresistance of La0.80Sr0.15Ag0.05MnO3/x(CuO)

Abstract

The samples of La0.80Sr0.15Ag0.05MnO3/x(CuO) (x = 0, 0.05, 0.10, 0.15, 0.20) were prepared by the solid-state reaction method, and the structure of the samples was detected by X-ray diffraction (XRD), scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS), electric transport mechanism, and magnetoresistance enhancement, and the temperature stability of magnetoresistance of the samples was studied through resistivity–temperature (ρ-T) curves, ρ-T fitted curves, and magnetoresistance–temperature (MR-T) curves. The results indicate that ρ-T data can be fitted by the formula ρ = ρ 0 + AT 2 very well, and the electric transport mechanism of all the samples in metal-like area is the scattering of single magneton upon spin electron; the magnetoresistance of composite samples is far larger than that of the original material, and the MR peak value of the sample with x = 0.20 is nearly 4 times as large as that of the sample with x = 0; composite samples have comparatively good temperature stability of magnetoresistance in the temperature range of 200–260 K, and the magnetoresistance of the sample with x = 0.15 almost does not change with temperature and keeps at (5.03 ± 0.20) % in the temperature range of 210–260 K.