Study of magnetic and magnetocaloric properties of calcium doped La0.97-xCaxHo0.03MnO3 compound

This study reports the magnetic and magnetocaloric properties of different concentrations of alkaline earth metal, such as Ca-doped La0.97-xCaxHo0.03MnO3 (x = 0.3, 0.33, and 0.37) composites, which were synthesized via autocombustion technique. The second-order paramagnetic-to-ferromagnetic phase transition temperature appeared at the temperature-dependent field-cooled magnetization curve. The result shows an increase in the Curie temperature of the compound with Ca2+ doping. In addition, increasing the Ca2+ doping concentration further increased the change in magnetic entropy, - triangle S-M, up to 0.206 J kg(-1) K-1, resulting in a higher RCP value up to 30 J kg(-1) at x = 0.37. This work's key aspect is demonstrating the potentiality of enhancing the magnetocaloric effect in the framework via the spin coupling mechanism of Ca2+-doped rare-earth perovskite compounds.