Phase transition in a 2-dimensional Heisenberg model
Statistical Mechanics
2009-11-07 v1
Abstract
We investigate the two-dimensional classical Heisenberg model with a nonlinear nearest-neighbor interaction V(s,s')=2K[(1+s.s')/2 ]^p. The analogous nonlinear interaction for the XY model was introduced by Domany, Schick, and Swendsen, who find that for large p the Kosterlitz-Thouless transition is preempted by a first-order transition. Here we show that, whereas the standard (p=1) Heisenberg model has no phase transition, for large enough p a first-order transition appears. Both phases have only short range order, but with a correlation length that jumps at the transition.
Keywords
Cite
@article{arxiv.cond-mat/0201174,
title = {Phase transition in a 2-dimensional Heisenberg model},
author = {Henk W. J. Bloete and Wenan Guo and Henk J. Hilhorst},
journal= {arXiv preprint arXiv:cond-mat/0201174},
year = {2009}
}
Comments
6 pages, 5 encapsulated postscript figures; to appear in Physical Review Letters