Influence of Nonstoichiometry on Magnetocaloric Effect in (La_0.7Ca_0.3)_{1 - x}Mn_1+xO₃

Abstract

Magnetocaloric eect in (La0.7Ca0.3)1−xMn1+xO3 manganites with x = 0, 0.1, 0.2 has been investigated. It is found a strong inuence of nonstoichiometry caused by excessive manganese on the magnetic entropy change. The magnetocaloric eect was evaluated from the isothermal curves of spontaneous magnetization versus the applied magnetic eld by using the well-known thermodynamical Maxwell relation. The maximum entropy value,