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Integrable Extended Hubbard Hamiltonians from Symmetric Group Solutions

Fabrizio Dolcini·Arianna Montorsi
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Abstract

We consider the most general form of extended Hubbard Hamiltonian conserving the total spin and number of electrons, and find all the 1-dimensional completely integrable models which can be derived from first degree polynomial solution of the Yang-Baxter equation. It is shown that such models are 96. They are identified with the 16-dimensional representation of a new class of solutions of symmetric group relations, acting as generalized permutators. As particular examples, the EKS and some other known models are obtained.

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Fabrizio Dolcini, Arianna Montorsi. 1999-12-17. Integrable Extended Hubbard Hamiltonians from Symmetric Group Solutions. https://arxiv.org/abs/cond-mat/9912321

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