Abstract :
An enhanced magnetoresistance and a two-fold effect result from impurity dopant were observed in composites of La0.67Ca0.33MnO3/YSZ and La0.67Ca0.33MnO3/Fe3O4. Where YSZ represents yttria-stabilized zirconia and the doping level of both YSZ and Fe3O4 is 1 mol%. Different electrical and magnetic transport properties, in particular a lower field magnetization behavior, were observed between pure La0.67Ca0.33MnO3 and the impurity doped La0.67Ca0.33MnO3 composites. Compared with pure La0.67Ca0.33MnO3, a possible interpretation is presented by considering the influences of YSZ and Fe3O4 on the structure of grain boundaries and/or surfaces of La0.67Ca0.33MnO3grains.
