TY - JOUR
T1 - Griffiths-McCoy singularities in random quantum spin chains
T2 - Exact results
AU - Iglói, Ferenc
AU - Kovács, István A.
PY - 2008/4/8
Y1 - 2008/4/8
N2 - 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 exactly calculated 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. The relation between the Dyson-Schmidt technique and the strong disorder renormalization group method is also discussed.
AB - 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 exactly calculated 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. The relation between the Dyson-Schmidt technique and the strong disorder renormalization group method is also discussed.
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U2 - 10.1103/PhysRevB.77.144203
DO - 10.1103/PhysRevB.77.144203
M3 - Article
AN - SCOPUS:42049107357
SN - 1098-0121
VL - 77
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 14
M1 - 144203
ER -