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Exact Electron-Pairing Ground States of Tight-Binding Models with Local Attractive Interactions

Akinori Tanaka
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Abstract

We present a class of exactly solvable models of correlated electrons. The models are defined in any dimension $d$ and consist of electron-hopping terms and local attractive interactions between electrons. For each even number of electrons less than or equal to $1/(d+1)$-filling, we find the exact ground state in which all electrons form pairs of a certain type, and thus the models exhibit an electron-pair condensation.

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Akinori Tanaka. 2003-10-27. Exact Electron-Pairing Ground States of Tight-Binding Models with Local Attractive Interactions. https://doi.org/10.1143/jpsj.73.1107

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