Electrical transport and magnetic properties in La0.7Sr0.3MnO3 and SrFe12O19 composite system

La0.7Sr0.3MnO3 (LSMO) and SrFe12O19 (SFO) samples were synthesized by chemical coprecipitation method. The composites of (1 − x)LSMO:xSFO (x is mass%) were prepared using solid-state cosintering. The microstructure, electrical transport, and magnetic properties of the derived composites were systematically investigated. Compared with pure LSMO, the enhancement of low-field magnetoresistance (LFMR) is observed in the composites. The magnetoresistance (MR) value at 300 K for the sample with x = 0.05 is about 2.9 times larger than that of the pure LSMO. The enhanced MR was attributed to the enhanced spin-dependent intergrain tunneling at the interfaces and grain boundaries due to the enhanced magnetic disorders and antiferromagnetic (AFM) couplings near boundaries between LSMO and SFO grains.