Abstract
A systematic investigation of structural, magnetic and magnetocaloric properties for Nd1-3xBax Ca-x SrxMnO3 (x = 0.11 and 0.133) manganites is reported. X-ray powder diffraction (XRD) patterns suggest that our samples crystallize in the orthorhombic perovskite structure with a Pbnm space group. Magnetization temperature dependence under the field-cooled cooling (FCc), field-cooled warming (FCw) and zero-field-cooling (ZFC) modes exhibit a ferromagnetic(FM)- paramagnetic(PM) phase transition a Tc temperature increasing from 120 K for x = 0.11-145 K for x = 0.133. An analysis using the Banerjee's criterion curves near T c indicates that x = 0.11 displays a second-order transition while x = 0.133 displays a first order magnetic phase transition. The analysis is further confirmed by the phenomenological universal curves of the normalized entropy variation as a function of resealed temperature. The maximum magnetic entropy change (-Delta S-M(max)) and relative cooling power (RCP) were estimated to 1.68 J /kg K and 89.45 J /kg for x = 0.11 and 4.11 J/kg K and 132.45 J /kg for x = 0.133 under 3T, respectively. The experimental approach mixing three different alkaline earth on the A-site perovskite significantly improves the broadening of the magnetic entropy change temperature dependence and then the relative cooling refrigerant capacity. Such approach can be transferred to manganite showing ferromagnetic to paramagnetic phase transition near room temperature for magnetic refrigeration application.