Modeling the Magnetocaloric Effect of La0.8MnO3 by the Mean-Field Theory
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In this research paper, our central focus is upon the investigation of the mean-field approach based on the Bean-Rodbell model applied to the magnetic properties of the compound La0.8MnO3. Using the isotherm, we determined the value of the mean-field exchange parameter λ. After using a MATLAB software, the values of J, g, and M0 were identified and compared with the experimental values. Another MFSS software running with MATLAB program was invested to determine the theoretical variation of magnetization as a function of magnetic field at different temperatures, the variation of magnetic entropy, and the nature of transition compared with the experimental values provided by data and Maxwell relation. A good accordance has been recorded between the experimental and theoretical curves. The values of ∆Smax and RCP which are equal to 3.63 J kg−1 K−1 and 83.38 J kg−1, respectively. They were determined by the Maxwell relation and were compared with those determined by the Bean-Rodbell model which are equal to 4.01 J kg−1 K−1 for ∆Smax and to 97.36 J kg−1 for the RCP at 2 T respectively.
KeywordsPerovskites Mean-field scaling Exchange parameter Magnetic entropy
The authors acknowledge the support of the Tunisian Ministry of Higher Education and Scientific Research and within the framework of Tunisian-Portuguese cooperation in the field of scientific research and technology.
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