Structural, magnetic and magnetocaloric properties in Pr 0.5M 0.1Sr 0.4MnO 3 (M = Eu, Gd and Dy) polycristalline manganites

Abstract

Structural, magnetic and magnetocaloric properties of Pr 0.5M 0.1Sr 0.4MnO 3 (M = Eu, Gd and Dy) powder samples have been investigated by X-ray diffraction (XRD) and magnetic measurements. Our samples have been synthesized using the solid state reaction method at high temperature. Rietveld refinements of the X-ray diffraction patterns show that all our samples are single phase and crystallize in the distorted orthorhombic system with Pbnm space group. Magnetization measurements versus temperature in a magnetic applied field of 50 mT show that all our samples exhibit a paramagnetic–ferromagnetic transition with decreasing temperature. The Curie temperature T C is found to be 270 K, 258 K and 248 K for M = Eu, Gd and Dy, respectively. Arrott plots show that all our samples exhibit a second order magnetic phase transition. From the measured magnetization data of Pr 0.5M 0.1Sr 0.4MnO 3 (M = Eu, Gd and Dy) samples as a function of magnetic applied field, the associated magnetic entropy change |Δ S M| and the relative cooling power RCP have been determined. In the vicinity of T C, |Δ S M| reached, in a magnetic applied field of 1 T, maximum values of 1.37 J/kg K, 1.23 J/kg K and 1.18 J/kg K for M = Eu, Gd and Dy, respectively.