On evaluation of transverse spin fluctuations in quantum magnets
Abstract
A numerical method is described for evaluating transverse spin correlations in the random phase approximation. Quantum, spin-fluctuation corrections to sublattice magnetization are evaluated for the half-filled Hubbard antiferromagnet in two and three dimensions in the whole U/t range. Extension to the case of defects in the Hubbard AF is discussed, and the vacancy-induced enhancement in transverse spin fluctuation is obtained in the infinite-U limit for the spin vacancy problem in two dimensions, for vacancy concentration up to the percolation threshold. For low-U impurities, the overall spin fluctuation correction is found to be strongly suppressed, although surprisingly spin fluctuations are locally enhanced at the low-U sites.
Keywords
Cite
@article{arxiv.cond-mat/9802049,
title = {On evaluation of transverse spin fluctuations in quantum magnets},
author = {Avinash Singh},
journal= {arXiv preprint arXiv:cond-mat/9802049},
year = {2009}
}
Comments
7 pages, 6 figures