Giant magnetoresistance in lanthanum strontium yttrium manganese oxides (La1−xSrx−zYzMnO3)

Electron transport and magnetic properties of several compositions of the La 1−x Srx−zYzMnO 3 system have been investigated in order to explore the effect of yttrium substitution on the magnetoresistance and related properties of these manganates. Yttrium substitution lowers the Tc and the insulator—metal transition temperature, while increasing the peak resistivity. A comparison of the properties of La 1−x Srx−zYzMnO 3 with the corresponding La 1−x Cax−zYzMnO 3 compositions shows that the observed properties can be related to the average size of the A-site cations.