Critical behavior in hexagonal Y2Fe17: magnetic interaction crossover from 3D to 2D Ising model

Abstract

The critical behavior of single phase Y₂Fe₁₇ melt-spun ribbons with the Th₂Fe₁₇-type crystal structure has been studied around the transition temperature (T_C). This alloy undergoes a second-order ferromagnetic (FM)–paramagnetic (PM) phase transition at T_C = 301 K. Various techniques, such as the modified Arrott plot, Kouvel–Fisher method, and critical isotherm analysis, were used to determine the critical exponents that were found to be β = 0.226(3), γ = 1.296(2), and δ = 6.804(5). The universality class of the critical phenomenon in the Y₂Fe₁₇ ribbons can be explained with the help of the renormalization group theory approach, in which the magnetic properties show a feature changing from three (3D)- to two-dimensional (2D) Ising model. The first-principles calculations based on density functional theory qualitatively explain the experimental results, confirming the strong correlation between lattice atoms and critical behavior in magnetic intermetallic Y₂Fe₁₇.