Study of critical magnetic behavior around the ferromagnetic–paramagnetic phase transition of the half-doped perovskite Nd0.5Ba0.5CoO3

In this research paper, we have carried out an in-depth study of the critical phenomena at the FM–PM phase transition for Nd0.5Ba0.5CoO3 (NBCO). The FM–PM phase transition is identified as second order for our material. Moreover, the critical exponents of NBCO compound were estimated based on multiple techniques such as Kouvel–Fisher, modified Arrott plot method, and critical isotherm analysis. Therefore, the average values of the critical exponent and the critical temperature obtained by the various methods are (βmoy = 0.506; γmoy = 1.011; δmoy = 3.042; TC = 125.543). The obtained critical exponents are in agreement with the mean-field model. Furthermore, the exponent n as a function of temperature reveals the non-homogeneous nature of NBCO compound. According to the mean field theory, the magnetic entropy change (ΔSM vs. M2) was invested to determine the spontaneous magnetization (Mspont) values. Results match reasonably well with those obtained from the classical extrapolation of Arrott plots (μ0H/M vs. M2).