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arXiv · 0903.0462

Renormalization-group investigation of the S=1 random antiferromagnetic Heisenberg Chain

Péter Lajkó
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Abstract

We introduce variants of the Ma-Dasgupta renormalization-group approach for random quantum spin chains, in which the energy-scale is reduced by decimation built on either perturbative or non-perturbative principles. In one non-perturbative version of the method, we require the exact invariance of the lowest gaps, while in a second class of perturbative Ma-Dasgupta techniques, different decimation rules are utilized. For the S=1 random antiferromagnetic Heisenberg chain, both type of methods provide the same type of disorder dependent phase diagram, which is in agreement with density-matrix renormalization-group calculations and previous studies.

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Péter Lajkó. 2009-03-03. Renormalization-group investigation of the S=1 random antiferromagnetic Heisenberg Chain. https://doi.org/10.1142/s0129183106010169

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