Structural, magnetic and transport properties of Sc-doped La0.7Sr0.3MnO3

The Sc-doped La_0.7Sr_0.3MnO₃ polycrystallines were prepared by thermal decomposition of complexes of metal ions with ethylenediamine-tetraacetic acid (EDTA). The dependence of structural, magnetic and transport properties on Sc doping was investigated. Moderate Sc doping level results in a sharp drop in Curie temperature, an increase in resistance and enhancement of magnetoresistance effect. At temperatures aboveT _MI,R(T) can be described asR(T) = R ₀exp(T ₀/T)^1/4, which indicates that conduction takes place by hopping between the localized states. The experimental data reveal that the change in magnetoresistance property is related to the structure.