Modeling the magnetic isotherms of (La 0.56 Ce 0.14 )Sr 0.30 MnO 3 by a mean-field scaling method and estimation of magnetic entropy change

We report a study on the magnetic properties of the (La0.56Ce0.14)Sr0.30MnO3 perovskite, by a mean-field method. By scaling of the experimental magnetization data, the mean-field exchange parameter λ and the BS function of the equation of state BS[(H+Hexch)/T] are directly determined, as well as the order of the phase transition. The spin quantum number of the manganite has been also determined. The mean-field scaling has been used to estimate magnetic entropy change (−ΔSM) within the thermodynamics of the model and without using the usual numerical integration of a Maxwell relation. The maxima of the positive absolute value of (−ΔSM) upon variation of the applied magnetic field at 1 and 5T are about 1.68 and 5.04Jkg−1K−1, respectively. Satisfactory agreement between the mean-field model and experimental behavior has been found.