"Theoretical work on magnetocaloric effect in La<sub>0.75</sub>Ca<sub>0" by Mahmoud Aly HAMAD

Article Title

Theoretical work on magnetocaloric effect in La_0.75Ca_0.25MnO₃

Authors

Mahmoud Aly HAMAD, Physics Department, College of Science, Al-Jouf University, Al-Jouf, Skaka, P.O. Box 2014, Saudi Arabia

Keywords

magnetocaloric effect, model, magnetic entropy change, heat capacity change, relative cooling power

Abstract

In this work, a phenomenological model is applied to describe the magnetocaloric effect for the La_0.75Ca_0.25MnO₃ system near a second-order phase transition from a ferromagnetic to a paramagnetic state. Based on this model, it can predict the values of the magnetocaloric properties from calculation of magnetization as a function of temperature under different external magnetic fields. The magnetic entropy change reaches a peak of about 5.39 J/(kg·K) at 257 K upon 4 T applied field variation. The ∆S_M distribution is much more uniform than that of gadolinium, which is desirable for an Ericson-cycle magnetic refrigerator.