Heisenberg antiferromagnet on the square lattice for S>=1
Condensed Matter
2009-10-31 v1
Abstract
Theoretical predictions of a semiclassical method - the pure-quantum self-consistent harmonic approximation - for the correlation length and staggered susceptibility of the Heisenberg antiferromagnet on the square lattice (2DQHAF) agree very well with recent quantum Monte Carlo data for S=1, as well as with experimental data for the S=5/2 compounds Rb2MnF4 and KFeF4. The theory is parameter-free and can be used to estimate the exchange coupling: for KFeF4 we find J=2.33 +- 0.33 meV, matching with previous determinations. On this basis, the adequacy of the quantum nonlinear sigma model approach in describing the 2DQHAF when S>=1 is discussed.
Keywords
Cite
@article{arxiv.cond-mat/9804245,
title = {Heisenberg antiferromagnet on the square lattice for S>=1},
author = {Alessandro Cuccoli and Valerio Tognetti and Paola Verrucchi and Ruggero Vaia},
journal= {arXiv preprint arXiv:cond-mat/9804245},
year = {2009}
}
Comments
4 pages RevTeX file with 5 figures included by psfig