Magnetocaloric Effect and Critical Behavior Investigations in La0.45Pr0.2Sr0.35MnO3 Manganite Oxide

摘要

Structural, magnetic, and magnetocaloric effect (MCE) properties and the critical behavior of the La0.45Pr0.2Sr0.35MnO3 sample prepared by the sol-gel method have been investigated. The X-ray diffraction characterization reveals that our sample crystallizes in the orthorhombic structure with Pnma space group. Magnetization versus temperature measurement shows that our compound exhibits a ferromagnetic-paramagnetic transition. The Curie temperature is found to be 348 K. Close to this temperature, the maximum values of the magnetic entropy change (S-M) and the relative cooling power (RCP) are found to be 2.84 J/kg/K and 230 J/K under mu H-0 =5 T, respectively. The Arrott plots revealed that this compound exhibits a second-order magnetic phase transition at T-C. The critical behavior has been investigated by several techniques which are the modified Arrott plot method, the Kouvel-Fisher method, and the critical isotherm analysis. The obtained critical exponents , , and are consistent with those predictions of the mean-field model. Their reliability was confirmed by Widom's scaling relation, as well as the universal scaling hypothesis.