Predicting the magnetocaloric properties in Gd ion substitution on La_0.6-xGd_xSr_0.4MnO₃ (x = 0, 0.0125, 0.05, and 0.10) manganites synthesized via the sol-gel method

This study investigates the critical behavior analysis and predicting magnetocaloric properties of La_0.6-xGd_xSr_0.4MnO₃ manganites, focusing on the impact of varying gadolinium (Gd) doping levels (x = 0, 0.0125, 0.05, and 0.10). Using modified Arrott plots (MAPs) and the Kouvel–Fisher method, the critical exponents γ and β were determined, yielding values that indicate how Gd content influences magnetic phase transitions. Additionally, the magnetocaloric effect (MCE) was analyzed to assess the magnetic entropy change \(-\Delta {{\rm{S}}}_{{\rm{M}}}({\rm{T}})\) $-\mathrm{\Delta }{\mathrm{S}}_{\mathrm{M}}\left(\mathrm{T}\right)$ and the Temperature-Averaged Entropy Change \(({TEC})\) $\left(\mathit{TEC}\right)$ across different magnetic field changes. The results show that increasing Gd doping enhances the magnetocaloric response, suggesting potential applications in magnetic refrigeration. Overall, the study provides insights into optimizing these manganites for applications in high-temperature sensors, spintronics, and magnetic cooling.