We consider the two-dimensional randomly site diluted Ising model and the random-bond +/- J Ising model (also called the Edwards-Anderson model), and study their critical behavior at the paramagnetic-ferromagnetic transition. The critical behavior of thermodynamic quantities can be derived from a set of renormalization-group equations, in which disorder is a marginally irrelevant perturbation at the two-dimensional Ising fixed point. We discuss their solutions, focusing in particular on the universality of the logarithmic corrections arising from the presence of disorder. Then, we present a finite-size scaling analysis of high-statistics Monte Carlo simulations. The numerical results confirm the renormalization-group predictions, and in particular the universality of the logarithmic corrections to the Ising behavior due to quenched dilution.
|Autori interni:||VICARI, ETTORE|
|Autori:||Hasenbusch M; Toldin FP; Pelissetto A; Vicari E|
|Titolo:||Universal dependence on disorder of two-dimensional randomly diluted and random-bond +/- J Ising models|
|Anno del prodotto:||2008|
|Digital Object Identifier (DOI):||10.1103/PhysRevE.78.011110|
|Appare nelle tipologie:||1.1 Articolo in rivista|