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A Model of Strongly Correlated Electrons with Condensed Resonating-Valence-Bond Ground States

Akinori Tanaka
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Abstract

We propose a new exactly solvable model of strongly correlated electrons. The model is based on a $d$-$p$ model of the CuO$_2$ plane with infinitely large repulsive interactions on Cu-sites, and it contains additional correlated-hopping, pair-hopping and charge-charge interactions of electrons. For even numbers of electrons less than or equal to 2/3-filling, we construct the exact ground states of the model, all of which have the same energy and each of which is the unique ground state for a fixed electron number. It is shown that these ground states are the resonating-valence-bond states which are also regarded as condensed states in which all electrons are in a single two-electron state. We also show that the ground states exhibit off-diagonal long-range order.

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Akinori Tanaka. 2003-11-17. A Model of Strongly Correlated Electrons with Condensed Resonating-Valence-Bond Ground States. https://doi.org/10.1088/0305-4470%2F37%2F5%2F007

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