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Dynamical dimer-dimer correlation functions from exact diagonalization

Ralph Werner
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Abstract

A regularization method is presented to deduce dynamic correlation functions from exact diagonalization calculations. It is applied to dimer-dimer correlation functions in quantum spin chains relevant for the description of spin-Peierls systems. Exact results for the XY model are presented. The analysis draws into doubt that the dimer-dimer correlation functions show the same scale invariance as spin-spin correlation functions. The results are applied to describe the quasi-elastic scattering in CuGeO$_3$.

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Ralph Werner. 2000-06-09. Dynamical dimer-dimer correlation functions from exact diagonalization. https://doi.org/10.1103/physrevb.63.174416

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