Magnetocaloric effect and critical behavior of the La0.75Ca0.1Na0.15MnO3 compound

In this paper, we have studied the critical behavior and the magnetocaloric effect (MCE) simulation for the La0.75Ca0.1Na0.15MnO3 (LCNMO) compound at the second order ferromagnetic-paramagnetic phase transition. The optimized critical exponents, based on the Kouvel-Fisher method, were found to be: beta = 0.48 and gamma = 1. These obtained values supposed that the Mean Field Model (MFM) is the proper model to analyze adequately the MCE in the LCNMO sample. The isothermal magnetization M(H, T) and the magnetic entropy change -Delta S-M(H, T) curves were successfully simulated using three models, namely the Arrott-Noakes equation (ANE) of state, Landau theory, and MFM. The framework of the MFM allows us to estimate magnetic entropy variation in a wide temperature range within the thermodynamics of the model and without using the usual numerical integration of Maxwell relation.

Automated summary

In this study, the critical behavior and magnetocaloric effect (MCE) simulation of La0.75Ca0.1Na0.15MnO3 (LCNMO) compound at the second order ferromagnetic-paramagnetic phase transition were investigated. The optimized critical exponents, beta = 0.48 and gamma = 1, were obtained using the Kouvel-Fisher method, suggesting that the Mean Field Model (MFM) is a suitable model for analyzing the MCE in the LCNMO sample. The isothermal magnetization M(H, T) and magnetic entropy change -Delta S-M(H, T) curves were successfully simulated using the Arrott-Noakes equation of state, Landau theory, and MFM, allowing for estimation of magnetic entropy variation in a wide temperature range.