Portal de Periódicos da CAPES

Artigo Acesso aberto Produção Nacional

BIBTEX RIS

Weak versus strong universality in the two-dimensional random-bond Ising ferromagnet

1996; American Physical Society; Volume: 54; Issue: 14 Linguagem: Inglês

10.1103/physrevb.54.r9616

1095-3795

F. D. A. Aarão Reis, S. L. A. de Queiroz, Raimundo R. dos Santos,

Opinion Dynamics and Social Influence

We address the issue of universality in two-dimensional disordered Ising systems, by considering long, finite-width strips of ferromagnetic Ising spins with randomly distributed couplings. We calculate the free energy and spin-spin correlation functions (from which averaged correlation lengths, $\xi^{ave}$, are computed) by transfer-matrix methods. An {\it ansatz} for the size-dependence of logarithmic corrections to $\xi^{ave}$ is proposed. Data for both random-bond and site-diluted systems show that pure system behaviour (with $\nu=1$) is recovered if these corrections are incorporated, discarding the weak--universality scenario.