Magnetoresistance temperature dependence of LSMO and LBMO perovskite manganites

AbstractLa۰.۷Sr۰.۳MnO۳ (LSMO) and La۰.۷Ba۰.۳MnO۳ (LBMO) Polycrystalline manganite nanoparticles were prepared by combustion method using glycine fuel. The ignition process was done at ۳۶۰ °C and ۳۳۰ °C for LSMO and LBMO, respectively. Both of the samples have rhombohedral structure using XRD analysis. The reduction is observed in electrical resistivity when external magnetic field is applied during the decrease in temperature from ۳۰۰ to ۸۹ °K, which is due to the tunneling between particles. The magnetoresistance (MR) of samples was measured in this range of temperature in both the presence and absence of a magnetic field of about ۱۰ kG. The colossal role of a kind of extrinsic MR which is ۱۹% and ۲۲% for LSMO and LBMO, respectively, has been investigated in this research. The metal–insulator transition temperature of ۲۰۰ °K is recorded for LBMO.

کلیدواژه ها:

Manganites ، Magnetoresistance ، Low temperature ، Combustion method