Real-space imaging of magnetic phase transformation in single crystalline Sm–Ca–Sr based manganite compound

Abstract

Low-temperature-high-magnetic field magnetic force microscopy studies on colossal magnetoresistance material Sm0.5Ca0.25Sr0.25MnO3 have been carried out. These measurements provide real-space visualization of antiferromagnetic–ferromagnetic (AFM–FM) transition on sub-micron length scale and explain the presence of AFM–FM transition in the temperature-dependent magnetization measurements, but the absence of corresponding metal–insulator transition in temperature-dependent resistivity measurements at the low magnetic field. Distribution of transition temperature over the scanned area indicates towards the quench disorder broadening of the first-order magnetic phase transition. It shows that the length scale of chemical inhomogeneity extends over several micrometers.