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Two Generalizations of $η$ Pairing in Extended Hubbard Models

Hui Zhai
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Abstract

A rigorous result about Hubbard model obtained by C.N.Yang [Phys.Rev.Lett.63,2144(1989)] is generalized to two kinds of extended Hubbard models. One is the Hubbard model in two-dimensional triangular lattice, and the other is the Hubbard model for high spins fermions. We obtain the conditions under which a modified $η$-pairing operator is an eigen-operator, thus these models have a series of eigenstates possessing off-diagonal long-range order.

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Hui Zhai. 2005-02-21. Two Generalizations of $η$ Pairing in Extended Hubbard Models. https://doi.org/10.1103/physrevb.71.012512

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