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arXiv · 0803.2617

Griffiths-McCoy singularities in random quantum spin chains: Exact results

Ferenc Iglói·István A. Kovács
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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 Fréchet form. Relation between the Dyson-Schmidt technique and the strong disorder renormalization group method is also discussed.

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Ferenc Iglói, István A. Kovács. 2008-03-18. Griffiths-McCoy singularities in random quantum spin chains: Exact results. https://doi.org/10.1103/physrevb.77.144203

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