Strongly disordered spin ladders
Abstract
The effect of quenched disorder on the low-energy properties of various antiferromagnetic spin ladder models is studied by a numerical strong disorder renormalization group method and by density matrix renormalization. For strong enough disorder the originally gapped phases with finite topological or dimer order become gapless. In these quantum Griffiths phases the scaling of the energy, as well as the singularities in the dynamical quantities are characterized by a finite dynamical exponent, z, which varies with the strength of disorder. At the phase boundaries, separating topologically distinct Griffiths phases the singular behavior of the disordered ladders is generally controlled by an infinite randomness fixed point.
Cite
@article{arxiv.cond-mat/0112261,
title = {Strongly disordered spin ladders},
author = {R. Mélin and Y. -C. Lin and P. Lajkó and H. Rieger and F. Iglói},
journal= {arXiv preprint arXiv:cond-mat/0112261},
year = {2009}
}
Comments
11 pages, 15 figures, PRB accepted for publication