Investigation of the critical properties near room temperature in La0.7Ca0.2Ba0.1MnO3 manganite

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Enhancement of magnetocaloric properties around room temperature in (1-x)La0.7Ca0.25Sr0.05MnO3/xLa0.7Ca0.2Sr0.1MnO3 system (0 ≤ x ≤ 1)

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Magnetic, magnetocaloric and critical behavior investigation of La0.69Dy0.01Ca0.3MnO3

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Correlation between critical properties and magnetocaloric effect using phenomenological model in La 0.7 Ca 0.2 Ba 0.1 MnO 3 compound

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Physical properties of La0.7Ca0.2Sr0.1MnO3 manganite: a comparison between sol–gel and solid state process

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Effect of elaborating method on magnetocaloric properties of La 0.7 Ca 0.2 Ba 0.1 MnO 3 manganite

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Adiabatic temperature change, magnetic entropy change and critical behavior near the ferromagnetic–paramagnetic phase transition in La0.7(Ca,Sr)0.3MnO3 perovskite

A systematic study of the magnetocaloric effect in La0.7Ca0.15Sr0.15MnO3 perovskite has been performed by both direct and indirect measurement techniques. In particular, the adiabatic temperature change has been measured by a purpose-built probe suitable for laboratory-scale samples, while magnetic measurements were carried out by standard magnetometric techniques. The observation of the effective behavior of the studied systems in adiabatic conditions and the significant value of the isothermal entropy variation indicate that La0.7Ca0.15Sr0.15MnO3 could be considered as a potential candidate for application in magnetic refrigeration around room temperature. Moreover, the critical exponents (γ, β and δ) determined using the Kouvel–Fisher method, the modified Arrott plot and the critical isotherm analysis are in good agreement with the theoretical prediction of the 3D-Ising model, indicating that the magnetic interactions are of short-range nature

Investigation of the magnetic, electronic and magnetocaloric properties of La0.7(Ca,Sr)0.3Mn1-xGdxO3 manganites

La0.7(Ca,Sr)0.3Mn1-xGdxO3 (with x=0; x=2% and x=6%) manganites samples have been studied by several techniques including X-ray diffraction (XRD), Scanning Electron Microscopy (SEM),55Mn and 139La nuclear magnetic resonance (NMR) spectroscopy and magnetometric measurements. The X-ray powder diffraction shows that all the prepared samples are single phase. La0.7Ca0.15Sr0.15MnO3 manganite is crystallized in the rhombohedral structure, whereas a structural transition towards orthorhombic system is observed for x≥ 2%. Magnetization as a function of temperature shows that all samples exhibit a ferromagnetic (FM)-paramagnetic (PM) phase transition. Gadolinium doping in Manganese site was found to induce a strong initial decrease of the Curie temperature TC at moderate Gd concentrations, followed by some levelling off at further doping, possibly due to the development of spatial correlations among the Gd impurities. The single double-exchange-narrowed 55Mn NMR line, though broadened by Gd, demonstrates a metallic state in all samples. The current manganites exhibit a second-order magnetic phase transition at TC, which is also confirmed by the criterion of Banerjee. In addition, the normalized entropy change curves of all the compounds collapse onto a universal master curve, a further signature of a second-order transition. The Gd-doped compounds undergo a large magnetocaloric effect, with an enhanced width TFWHM of the entropy change peak as compared to the Gd-free materials, and have consequently potential applications in magnetic refrigeratio