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Itineracy Effects on Spin Correlations in 1D Mott Insulators

M. J. Bhaseen·F. H. L. Essler·A. Grage
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Abstract

We consider spin correlations in the one dimensional half filled repulsive Hubbard model. For very large values of the on-site repulsion U the spin correlations are dominated by virtual hopping processes of electrons and are described in terms of a spin-1/2 Heisenberg chain. As U is decreased real hopping processes of electrons become important and eventually dominate the spin response. We discuss the evolution of the dynamical structure factor as a function of U. We comment on the relevance of our results for inelastic neutron scattering experiments on quasi-1D materials.

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M. J. Bhaseen, F. H. L. Essler, A. Grage. 2003-12-02. Itineracy Effects on Spin Correlations in 1D Mott Insulators. https://doi.org/10.1103/physrevb.71.020405

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