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Crossed spin-1/2 Heisenberg chains as a quantum impurity problem

S. A. Reyes·A. M. Tsvelik
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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 coupling. The result reveals a power law decay with a nonuniversal exponent.

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S. A. Reyes, A. M. Tsvelik. 2005-08-23. Crossed spin-1/2 Heisenberg chains as a quantum impurity problem. https://doi.org/10.1103/physrevlett.95.186404

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