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Strongly correlated hopping and many-body bound states

J. Vidal·B. Doucot
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Abstract

We study a system in which the quantum dynamics of electrons depend on the particle density in their neighborhood. For any on-site repulsive interaction, we show that the exact two-body and three-body ground states are bound states. We also discuss the finite density case in a mean-field framework and we show that the system can undergo an unusual transition from an effective attractive interaction to a repulsive one, when varying the electron density.

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J. Vidal, B. Doucot. 2001-10-02. Strongly correlated hopping and many-body bound states. https://doi.org/10.1103/physrevb.65.045102

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