Quenched bond randomness in marginal and non-marginal Ising spin models in 2D

Nikolaos G. Fytas, A. Malakis, I. A. Hadjiagapiou

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

We investigate and contrast, via entropic sampling based on the Wang–Landau algorithm, the effects of quenched bond randomness on the critical behavior of two Ising spin models in 2D. The random bond version of the superantiferromagnetic (SAF) square model with nearest- and next-nearest-neighbor competing interactions and the corresponding version of the simple Ising model are studied, and their general universality aspects are inspected by means of a detailed finite size scaling (FSS) analysis. We find that the random bond SAF model obeys weak universality, hyperscaling, and exhibits a strong saturating behavior of the specific heat due to the competing nature of interactions. On the other hand, for the random Ising model we encounter some difficulties as regards a definite discrimination between the two well-known scenarios of the logarithmic corrections versus the weak universality. However, a careful FSS analysis of our data favors the field theoretically predicted logarithmic corrections.
Original languageEnglish
Article numberP11009
JournalQuenched bond randomness in marginal and non-marginal Ising spin models in 2D
Volume2008
DOIs
Publication statusPublished - 11 Nov 2008

    Fingerprint

Bibliographical note

The full text is not available on the repository

Cite this