A study on the magnetothermal properties and magnetocaloric effect in [formula omitted] ([formula omitted

Abstract

In this study, we investigate the Gd1−xCexMn2Ge2 system with x=0.17 and x=0.33 using the mean field theory. Ab-initio based calculations are used to determine the density of states at Fermi energy, D(Ef), and Debye temperature θD for GdMn2Ge2 main compound. Our aim is to determine key properties such as magnetization, magnetic heat capacity, and the magnetocaloric effect main aspects including both isothermal entropy change and adiabatic temperature change. We examine these parameters under various conditions by applying different field changes up to 6 T and at temperatures spanning a range up to 400 K. The two systems have a Curie temperature, that is around room temperature (around 330 K). Using the trapezoidal method, the Gd1−xCexMn2Ge2 systems exhibit a maximum ΔSm value of 0.79 J/mol K for ΔH=6 T, and a ΔT value of an average 1.3 K/Tesla. In our study, the relative cooling power (RCP) was investigated and moreover, we examined the nature of phase transitions using universal curves and Arrott plots to confirm that the nature of phase transition at Tc in this system corresponds to a second-order phase transition (SOPT). The influence of high magnetic fields on the magnetization was also examined, and it showed first-order phase transition (FOPT) at low temperatures and high fields. Additionally, due to FOPT, a change in magnetic order from ferrimagnetism to ferromagnetism took place.