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Numerical renormalization group study of random transverse Ising models in one and two space dimensions

Y. -C. Lin·N. Kawashima·F. Igloi·H. Rieger
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Abstract

The quantum critical behavior and the Griffiths-McCoy singularities of random quantum Ising ferromagnets are studied by applying a numerical implementation of the Ma-Dasgupta-Hu renormalization group scheme. We check the procedure for the analytically tractable one-dimensional case and apply our code to the quasi-one-dimensional double chain. For the latter we obtain identical critical exponents as for the simple chain implying the same universality class. Then we apply the method to the two-dimensional case for which we get estimates for the exponents that are compatible with a recent study in the same spirit.

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Y. -C. Lin, N. Kawashima, F. Igloi, H. Rieger. 1999-12-06. Numerical renormalization group study of random transverse Ising models in one and two space dimensions. https://doi.org/10.1143/ptps.138.479

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