Structural, magnetocaloric, electrical properties and theoretical investigations in manganite La0.67Sr0.1Ca0.23MnO3 type perovskite.
Abstract
The structural, magnetocaloric and electrical properties of La0.67Sr0.1Ca0.23MnO3 (LSCMO) perovskite have been studied. The sample was prepared by conventional solid-state ceramics route. X-ray diffraction revealed that the compound is in the rhombohedral phase with an R 3c space group. Magnetization as a function of temperature under 1, 2, 3, 4 and 5T magnetic fields showed that the sample exhibits a transition from a ferromagnetic (FM) to paramagnetic (PM) phase with increasing temperature. Magnetic entropy change, relative cooling power and specific heat for magnetic field variation were predicted with
the help of the phenomenological model. The maximum of the magnetic entropychange DSmax M and large relative cooling power (RCP) values in a magnetic field change of 5 Tare found to be 5.971 J kg 1 K 1 and 278.547 J kg 1, respectively at 294 K. It is suggested that LSCMO sample is a suitable candidate as a refrigerant at near room temperature region. Moreover, the dependence of electrical resistivity on temperature shows a metal -semiconductor transition at TM-Sc for LSCMO. The electrical resistivity is fitted with the phenomenological percolation model which is based on the phase segregation of ferromagnetic metallic clusters and paramagnetic insulating regions. Hence, we found that the estimated values of resistivity are in good agreement with experimental data.