Critical behavior around the ferromagnetic–paramagnetic phase transition in La2−xCex/2Erx/2NiMnO6 using an iterative approach

[Display omitted] •Landau theory has been exploited to generate isothermal M (H, T) curves near PM-FM phase transition.•An iterative method based on modified Arrott plot was used to determine critical exponents.•The β, γ and δ critical exponents are verified with various techniques.•The critical exponents identified (β, γ, and δ) do not belong to any universally recognized classes.•The obtained critical exponents fulfill Widom scaling relation. In this paper we investigate the critical aspects of our La2−xCex/2Erx/2NiMnO6 samples with (x = 0.00, 0.025 and 0.035) during the paramagnetic (PM) – ferromagnetic (FM) phase transition by observing the relationship between magnetization (M) and magnetic field (µoH). This approach relies on an iterative strategy that employs modified Arrott plots. Firstly the Landau theory was used to generate isothermal M (H, T) curves near the PM – FM phase transition. Afterwards, alternative methods were used to evaluate the critical exponents acquired for manganite materials, including the Kouvel-Fisher (KF) approach and the critical isotherm (CI) around TC. Furthermore, Widom’s scaling law (δ = 1 + γ/β) was employed to validate the precision of the critical exponent parameters. Additionally, the scaling formula identified by MH,ε=εβf±Hεβ+γ with ε = (T − TC)/TC was utilized to further validate the appropriateness of the obtained exponents. According to the scaling formula, two separate branches of the M-µoH-T curves were observed; one above and another below TC. Moreover, the exponents determined in this study did not belong to any universally recognized classes. These results suggest that the critical phenomenon in our samples, which was an inhomogeneous ferromagnet around TC, influenced by magnetic disorder due to oxygen vacancies, cannot be described within the framework of existing universality classes and probably belong to a separate class.