Exact results for quantum phase transitions in random XY spin chains
Condensed Matter
2009-10-28 v1
Abstract
The effect of disorder on the quantum phase transitions induced by a transverse field, anisotropy, and dimerization in XY spin chains is investigated. The low-energy behavior near the critical point is described by a Dirac-type equation with a random mass for which an exact analytic treatment is possible. Results obtained for the dynamical critical exponent, the specific heat, and transverse susceptibility agree with results recently obtained using a real space renormalization group decimation technique, supporting Fisher's claim that it is exact. A non-zero transverse field changes the universality class of the anisotropy transition.
Cite
@article{arxiv.cond-mat/9609195,
title = {Exact results for quantum phase transitions in random XY spin chains},
author = {Ross H. McKenzie},
journal= {arXiv preprint arXiv:cond-mat/9609195},
year = {2009}
}
Comments
5 pages, RevTeX + epsf, 2 figures.