The magnetic and caloric properties of La0.7Sr0.3Mn0.9Cu0.1O3 and La0.7Sr0.3Mn0.95Fe0.05O3 manganites with Curie temperatures equal to 270 and 307 K, respectively, have been studied experimentally. The direct method has been used to study the temperature dependences of the magnetocaloric effect in specimens when changing the magnetic field ΔH = 2 T. The magnitudes of magnetocaloric effect for La0.7Sr0.3Mn0.9Cu0.1O3 and La0.7Sr0.3Mn0.95Fe0.05O3 were ΔТ = 0.3 and 0.87 К, respectively. It is shown that the Curie temperature of the studied manganites is near room temperatures, which makes them promising candidates for use in magnetic cooling devices.
Pavlukhina et al. (Mon,) studied this question.