Transport Properties in La0.67Sr0.33Co1−xFexO3 System

In this paper the influence of Fe doping at Co-site on the electrical transport properties and the colossal magnetoresistance of La0.67Sr0.33Co1−xFexO3 is studied. The experimental results indicate that the electrical resistivity exhibits in low-doped (x≤0.10) samples while semiconducting behavior exhibits in high-doped (x=0.20, 0.30) samples. In addition, Fe doping weakens the MR peak near Tc but enhances the low-temperature MR. The origin of CMR in La0.67Sr0.33Co1−xFexO3 system is interpreted in terms of the spin-state transition induced by applied magnetic field.