Grain size effect on the critical behavior of the ferromagnetic transition in electronically phase separated La0.5Ca0.5MnO3

Abstract

Mixed valence manganese oxides (manganites) are known to exhibit intrinsic inhomogeneous magnetic states, which are influenced by a great variety of factors, including oxygen stoichiometry, nanostructuration and ceramic grain size. In this context, the prototypical half-doped compound La0.5Ca0.5MnO3was extensively studied. Here we reloaded the phase separated scenario, focusing on the thermodynamical critical behavior of this system at the paramagnetic - ferromagnetic transition and its correlation with the evolution of its ordering capabilities controlled through the ceramic grain size. Our findings establish a clear connection between the correlation length and the grain size, shedding light on the role of this parameter in the control of inhomogeneous magnetic ground states in manganites. Therefore it is possible to tailor fundamental physical properties as the scaling laws of the system just tuning the ceramic grain size.