Abstract
We have undertaken a systematic study of critical behavior in La0.67Sr0.33MnO3 nanoparticles, sintered at different temperatures (L6, L8, L10 and L12 sintered at 600 degrees C, 800 degrees C, 1000 degrees C, 1200 degrees C respectively), by magnetization measurements. The critical exponents are estimated by various techniques such as the Modified Arrott plot, Kouvel-Fisher plot and critical isotherm technique. Compared to standard models, the critical exponents are close to those expected by the Mean-field model (with beta = 0.5 gamma = 1, and delta = 3) for (L6, L8, and L10) samples and by the (3D) Heisenberg model (beta = 0.365, gamma = 1.336 and delta = 4.80) for L12 sample. We conclude that the reduction of grain size strongly influences the universality class. (C) 2017 Elsevier B. V. All rights reserved.