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On Quantum Groups in the Hubbard Model with Phonons

Bianca L. Cerchiai·Peter Schupp
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Abstract

The correct Hamiltonian for an extended Hubbard model with quantum group symmetry as introduced by A. Montorsi and M. Rasetti is derived for a D-dimensional lattice. It is shown that the superconducting SUq(2) holds as a true quantum symmetry only for D = 1 and that terms of higher order in the fermionic operators in addition to phonons are required for a quantum symmetric hamiltonian. The condition for quantum symmetry is "half filling" and there is no local electron-phonon coupling. A discussion of Quantum symmetries in general is given in a formalism that should be readily accessible to non Hopf-algebraists.

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BibTeXRIS

Bianca L. Cerchiai, Peter Schupp. 1995-10-13. On Quantum Groups in the Hubbard Model with Phonons. https://doi.org/10.1088/0305-4470%2F29%2F4%2F012

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