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Hubbard Models as Fusion Products of Free Fermions

Z. Maassarani
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Abstract

A class of recently introduced su(n) `free-fermion' models has recently been used to construct generalized Hubbard models. I derive an algebra defining the `free-fermion' models and give new classes of solutions. I then introduce a conjugation matrix and give a new and simple proof of the corresponding decorated Yang-Baxter equation. This provides the algebraic tools required to couple in an integrable way two copies of free-fermion models. Complete integrability of the resulting Hubbard-like models is shown by exhibiting their L and R matrices. Local symmetries of the models are discussed. The diagonalization of the free-fermion models is carried out using the algebraic Bethe Ansatz.

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Z. Maassarani. 1997-12-23. Hubbard Models as Fusion Products of Free Fermions. https://doi.org/10.1142/s0217979298001095

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