Griffiths-McCoy singularities in random quantum spin chains: Exact results
Disordered Systems and Neural Networks
2010-08-09 v1 Statistical Mechanics
Abstract
We consider random quantum (tight-binding, XX and Ising) spin chains in the off-critical region and study their Griffiths-McCoy singularities. These are obtained from the density of states of the low-energy excitations, which is calculated exactly by the Dyson-Schmidt method. In large finite systems the low-energy excitations are shown to follow the statistics of extremes and their distribution is given by the Fr\'echet form. Relation between the Dyson-Schmidt technique and the strong disorder renormalization group method is also discussed.
Cite
@article{arxiv.0803.2617,
title = {Griffiths-McCoy singularities in random quantum spin chains: Exact results},
author = {Ferenc Iglói and István A. Kovács},
journal= {arXiv preprint arXiv:0803.2617},
year = {2010}
}
Comments
7 pages, accepted for publication in Phys. Rev. B