Symmetries of an Extended Hubbard Model

Bianca L. Cerchiai; Peter Schupp

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arXiv · cond-mat/9605121

Symmetries of an Extended Hubbard Model

Bianca L. Cerchiai·Peter Schupp

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Abstract

An extended Hubbard model with phonons is considered on a D-dimensional lattice. The symmetries of the model are studied in various cases. It is shown that for a certain choice of the parameters a superconducting SU_q(2) holds as a true quantum symmetry - but only for D=1. In a natural basis the symmetry requires vanishing local phonon coupling; a quantum symmetric Hubbard model without phonons can then be obtained by a mean field approximation.

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Bianca L. Cerchiai, Peter Schupp. 1996-05-20. Symmetries of an Extended Hubbard Model. https://arxiv.org/abs/cond-mat/9605121

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