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arXiv:cond-mat/0507312 · Physical Review Letters

Crossed Spin- 1/2 Heisenberg Chains as a Quantum Impurity Problem

Sebastián A. Reyes, Alexei M. Tsvelik

Published Oct 27, 2005• 4 citations
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Abstract

Using equivalencies between different models we reduce the model of two spin-1/2 Heisenberg chains crossed at one point to the model of free fermions. The spin-spin correlation function is calculated by summing the perturbation series in the interchain interaction. The result reveals a power law decay with a nonuniversal exponent.
DOI
10.1103/physrevlett.95.186404

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