title: Static critical exponents of the ferromagnetic transition in spin glass re-entrant systems.
abstract: The static critical phenomenology near the Curie temperature of the re-entrant metallic alloys Au(0.81)Fe(0.19), Ni(0.78)Mn(0.22), Ni(0.79)Mn(0.21) and amorphous a-Fe(0.98)Zr(0.08) is studied using a variety of experimental techniques and methods of analysis. We have generally found that the values for the exponents α, β, γ and δ depart significantly from the predictions for the 3D Heisenberg model and are intermediate between these expectations and the values characterizing a typical spin glass transition. Comparing the exponents obtained in our work with indices for other re-entrant systems reported in the literature, a weak universality class may be defined where the exponents are distributed within a certain range around average values.
authors.affiliation: Instituto de Física, Universidade Federal do Rio Grande do Sul, PO Box 15051, 91501-970 Porto Alegre, RS, Brazil.
authors.forename: Cláudia M
authors.initials: CM
authors.lastname: Haetinger
authors.forename: Luis
authors.initials: L
authors.lastname: Ghivelder
authors.forename: Jacob
authors.initials: J
authors.lastname: Schaf
authors.forename: Paulo
authors.initials: P
authors.lastname: Pureur