Wang–Landau study of the random bond square Ising model with nearest- and next-nearest-neighbor interactions

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

    Research output: Contribution to journalArticle

    12 Citations (Scopus)

    Abstract

    We report results from a Wang–Landau study of the random bond square Ising model with nearest-neighbor (Jnn) and next-nearest-neighbor (Jnnn) antiferromagnetic interactions. We consider the case R = Jnn/Jnnn = 1 for which the competitive nature of interactions produces a sublattice ordering known as superantiferromagnetism and the pure system undergoes a second-order transition with a positive specific heat exponent α. For a particular disorder strength we study the effects of bond randomness and we find that, while the critical exponents of the correlation length ν, magnetization β, and magnetic susceptibility γ increase as compared to the pure model, the ratios β/ν and γ/ν remain unchanged. Thus, the disordered system obeys weak universality and hyperscaling similarly to other two-dimensional disordered systems. However, the specific heat exhibits an unusually strong saturating behavior which distinguishes the present case of competing interactions from other two-dimensional random bond systems studied previously.
    Original languageEnglish
    Article numberL07001
    JournalJournal of Statistical Mechanics: Theory and Experiment
    Volume2008
    DOIs
    Publication statusPublished - 24 Jul 2008

    Bibliographical note

    The full text is not available on the repository.

    Fingerprint

    Dive into the research topics of 'Wang–Landau study of the random bond square Ising model with nearest- and next-nearest-neighbor interactions'. Together they form a unique fingerprint.

    Cite this