Phase diagram and magnons in quasi-one-dimensional dipolar antiferromagnets
Abstract
We investigate antiferromagnetic spin chains, which are coupled by a weak antiferromagnetic exchange interaction on a hexagonal lattice. We particulary study the role of the dipole-dipole interaction within the framework of a Heisenberg model with nearest-neighbor exchange and additional dipolar interaction. We find several commensurate and incommensurate phases depending on the ratio of dipolar energy to interchain-exchange energy due to their competing qualtity. The ground-state analysis is supplemented by a stability analysis by means of a linear spin-wave theory. In comparison with experiments (CsMnBr_3, RbMnBr_3) we obtain good agreement for the energy gaps. From this we conclude, that the dipolar interaction is the most important source of anisotropy in these Mn-compounds.
Cite
@article{arxiv.cond-mat/9810402,
title = {Phase diagram and magnons in quasi-one-dimensional dipolar antiferromagnets},
author = {M. Hummel and C. Pich and F. Schwabl},
journal= {arXiv preprint arXiv:cond-mat/9810402},
year = {2009}
}
Comments
3 pages, 3 Postscript figures