Recent results on integrable electronic models

Alberto Anfossi; Fabrizio Dolcini; Arianna Montorsi

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Recent results on integrable electronic models

Alberto Anfossi·Fabrizio Dolcini·Arianna Montorsi

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Abstract

We review the approach of generalized permutator to produce a class of integrable quantum Hamiltonians, as well as the technique of Sutherland species (SS) to map a subclass of it into solvable spinless fermions models. In particular, we apply the above scheme to construct integrable interacting electron Hamiltonians: first we review the extended Hubbard case, discussing both ground state and thermodynamics; then we pass to constrained fermion models, generating 56 integrable cases, among which both supersymmetric t-J model and infinite U Hubbard model are obtained, as well as other physically interesting cases, such as a particular t-V model. For the latter we describe how the complete spectrum can be gained by means of SS technique. Finally we speculate about possible applications to spin S models.

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Alberto Anfossi, Fabrizio Dolcini, Arianna Montorsi. 2005-09-15. Recent results on integrable electronic models. https://arxiv.org/abs/cond-mat/0412532

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