Size-induced modification of magneto-transport properties in nanocrystalline Sm0.5Ca0.5MnO3 compound

• Magnetotransport properties of Sm0.5Ca0.5MnO3 nanocrystalline particles were studied.
• Activation energy remarkably modifies in nanoscale regime.
• Magnetoresistance increases in nanoparticles.

We report the electronic and magneto-transport behaviors of the nanocrystalline Sm0.5Ca0.5MnO3 compound and the results are compared with their bulk counterpart. Our experimental findings indicate that the insulating nature of Sm0.5Ca0.5MnO3 compound is found to reduce and the enhancement of magnetoresistance has been observed with the reduction of particle sizes. Resistivity of the nanocrystalline and bulk samples in different temperature regions are analyzed by considering the adiabatic small polaron hopping model. Our analysis of resistivity data suggests that the activation energy markedly reduces and magnetoresistance increases in nanoscale regime due to the pronounced surface effect.