Analysis of the Magnetization as a Function of the Magnetic Field at the Transition Temperature for La0.6Nd0.4Mn2Si2

We analyze in this study our experimental data for the magnetization (M) as a function of the magnetic field (H) at various constant temperatures for the multilayer structure of La 0.6Nd 0.4Mn 2Si 2 close to the ferromagnetic-antiferromagnetic transitions. This analysis is performed at the transition temperatures (Tc) for the M vs. H– Hc (Hc is the critical field) according to a power-law formula above and below Hc, and the values of the critical isotherm δ are deduced for La 0.6Nd 0.4Mn 2Si 2. We also calculate the magnetic field (H– Hc) dependence of the isothermal susceptibility χT at constant temperatures above and below Hc, and we obtain the critical behaviour of χT for this multilayer structure. Our δ values indicate that the ferromagnetic–antiferromagnetic transition in La 0.6Nd 0.4Mn 2Si 2 changes its character from a first order (discontinuous) toward a second-order (continuous) one as the constant temperature changes.