Magnetic Entropy Change in La0.57Nd0.1Sr0.13Ag0.2MnO3 by Means of Theoretical Models

In the present research work, a phenomenological model is applied to describe the magnetocaloric effect of the La 0.57 Nd 0.1 Sr 0.13 Ag 0.2 MnO 3 system near a second-order phase transition from ferromagnetic to paramagnetic state. Based on this model, the values of the magnetocaloric properties are predicted from the calculation of magnetization as a function of temperature under different external magnetic fields. The maximum magnetic entropy change ( - Δ S M max ) and the relative cooling power are found to be, respectively, 1.51 J kg −1 K −1 and 71.96 J kg −1 for H = 2 T , making this material a suitable candidate for magnetic refrigeration applications. The magnetic entropy change Δ S has been determined using the Landau theory consistent with the experimental ones. A master curve of the magnetic entropy change confirmed the second order of the magnetic phase transition.