Prediction of Magnetocaloric Effects of La_0.7Sr_0.3Mn_1-xCu_xO₃ Compounds (x = 0.08 and 0.12) Using a Phenomenological Model

In the present study, we present our investigation on the structure and magnetocaloric effect (MCE) of La_0.7Sr_0.3Mn_1−xCu_xO₃ (x = 0.08 and 0.12) compounds prepared by a conventional solid-state method. X-ray diffraction patterns indicate that the samples have a rhombohedral structure with the \( R\bar{3}c \) space group. The Curie temperature decreases with increasing Cu concentration. Using a phenomenological model, the MCE of the two samples was predicted from the experimental magnetization data measured at magnetic fields of 3 kOe, 5 kOe, 8 kOe, and 10 kOe. The type of second-order magnetic phase transition of the samples is confirmed by the collapse of the entire master curve of magnetic entropy change in the same plot. Our investigation on the magnetocaloric behavior of the title compounds suggests that they are suitable candidates for application to near-room temperature magnetic refrigeration.