Abstract
In the present work, we aim to analyze the magnetocaloric and electrical properties of (La0.75Nd0.25)(2/3)(Ca0.8Sr0.2)(1/3)MnO3 manganite prepared by solid-state method at high temperature. The experimental results of the magnetization show that the (La0.75Nd0.25)(2/3)(Ca0.8Sr0.2)(1/3)MnO3 compound exhibits a paramagnetic-ferromagnetic transition at T-C = 240 K. In addition to the experimental study, theoretical approaches are adopted to investigate the magnetocaloric behavior of this sample. The important parameters such as maximum entropy change, full width at half maximum (delta T-FWHM) and relative cooling power are explained qualitatively. The electrical properties of the studied sample have been investigated by using a complex impedance spectroscopy technique. These electrical measurements reveal that (La0.75Nd0.25)(2/3)(Ca0.8Sr0.2)(1/3)MnO3 sample exhibits a metallic behavior at low temperature and insulator one at high temperature. The temperature (T-MI) of the metalinsulator transition is found to be about 240 K. The effects of frequency, temperature and composition on permittivity epsilon', epsilon '' and dielectric loss (tan delta) have been also discussed in terms of hopping of charge carriers between Mn3+ and Mn4+ ions.