Magnetic field dependence of Griffith phase and critical behavior in La0.8Ca0.2MnO3 nanoparticles

Abstract In this work, the La 0.8 Ca 0.2 MnO 3 nanoparticles of ∼30 nm were prepared by a sol-gel method, and their magnetic properties were investigated. The sample shows a paramagnetic-to-ferromagnetic phase transition at about 214 K. The Griffiths phase, which is identified by the downturn of the inverse susceptibility versus temperature plot from the Curie-Weiss law, is suppressed with the increase of the applied magnetic field strength such as 10 kOe. From the study of magnetic properties in terms of Arrot plots, the nature of magnetic transitions is found to be of second order. The critical behavior of La 0.8 Ca 0.2 MnO 3 nanoparticles was studied around its Curie temperature. The estimated critical exponents were close to those expected for mean-field model. These critical exponents fulfill the Widom scaling relation, implying the reliability of our values.