Ground State Structure of Random Magnets
Disordered Systems and Neural Networks
2007-05-23 v5 Statistical Mechanics
Abstract
Using exact optimization methods, we find all of the ground states of +/- h random-field Ising magnets (RFIM) and of dilute antiferromagnets in a field (DAFF). The degenerate ground states are usually composed of isolated clusters (two-level systems) embedded in a frozen background. We calculate the paramagnetic response (sublattice response) and the ground state entropy for the RFIM (DAFF) due to these clusters. In both two and three dimensions there is a broad regime in which these quantities are strictly positive, even at irrational values of h/J (J is the exchange constant).
Cite
@article{arxiv.cond-mat/9801108,
title = {Ground State Structure of Random Magnets},
author = {Sorin Bastea and Philip M. Duxbury},
journal= {arXiv preprint arXiv:cond-mat/9801108},
year = {2007}
}
Comments
REVTEX, 5 included figures (1 color)