Magnetocaloric effect and refrigerant capacity in Sm1−xSrxMnO3 (x = 0.42, 0.44, 0.46) manganites

Sm1−xSrxMnO3 (SSMO) with x ∼ 0.44 shows a multi-critical phase diagram which includes antiferromagnetic, charge ordering, and ferromagnetic transitions that give rise to large magnetoresistive and magnetocaloric effects. In this study, we systematically investigated the magnetic transitions, magnetocaloric effect (MCE), and refrigerant capacity (RC) in polycrystalline Sm1−xSrxMnO3 (x = 0.42, 0.44, 0.46) samples prepared by a standard ceramic method. Magnetization measurements and Arrott plot analyses reveal a first-order ferromagnetic transition for all samples investigated, with TC = 130 K, 134 K, and 133 K for x = 0.42, 0.44, and 0.46, respectively. The largest peak entropy change of −ΔSM = 4.61 J/kg K for a field change of μ0ΔH = 5 T is observed for the x = 0.44 composition around its Curie temperature of 134 K. After correcting for hysteretic losses of ∼15% – 30% engendered by the first order nature of the transition, sizable RC values of 151.42 J/kg, 140.15 J/kg, and 135.91 J/kg are still observed for x = 0.42, 0.44, and 0.46, respectively.