Phase diagram of an Ising model with competitive interactions on a Husimi tree and its disordered counterpart
Abstract
We consider an Ising competitive model defined over a triangular Husimi tree where loops, responsible for an explicit frustration, are even allowed. After a critical analysis of the phase diagram, in which a ``gas of non interacting dimers (or spin liquid) - ferro or antiferromagnetic ordered state'' transition is recognized in the frustrated regions, we introduce the disorder for studying the spin glass version of the model: the triangular +/- J model. We find out that, for any finite value of the averaged couplings, the model exhibits always a phase transition, even in the frustrated regions, where the transition turns out to be a glassy transition. The analysis of the random model is done by applying a recently proposed method which allows to derive the upper phase boundary of a random model through a mapping with a corresponding non random one.
Cite
@article{arxiv.cond-mat/0611654,
title = {Phase diagram of an Ising model with competitive interactions on a Husimi tree and its disordered counterpart},
author = {Massimo Ostilli and Farrukh Mukhamedov and José F. F. Mendes},
journal= {arXiv preprint arXiv:cond-mat/0611654},
year = {2009}
}
Comments
19 pages, 11 figures; content changed