Griffiths-McCoy singularities in random quantum spin chains: Exact results
نویسندگان
چکیده
منابع مشابه
Griffiths-McCoy singularities in random quantum spin chains: Exact results
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...
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ژورنال
عنوان ژورنال: Physical Review B
سال: 2008
ISSN: 1098-0121,1550-235X
DOI: 10.1103/physrevb.77.144203