منابع مشابه
Symmetries and mean-field phases of the extended Hubbard model.
The two-dimensional extended Hubbard model that includes a nearestneighbor Heisenberg interaction is studied using a mean-field theory where quasiparticles are defined by an U(8) group of canonical transformations. The theory is a generalization of the ordinary BCS theory, and Balian and Werthamer’s theory of 3He that permits both broken gauge, spin and sublattice symmetry. This allows us to in...
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The past two decades have witnessed the discoveries of several new classes of novel electronic materials. Ranging from conducting polymers through charge transfer solids and inorganic chain compounds to organic and high temperature superconductors, these materials have in common two important, unusual properties. First, their electronic structures are strongly anisotropic, in some cases (e.g., ...
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One dimensional chiral Hubbard model reduces to the Haldane-Shastry spin chain at half-filling with large but finite on-site energy U . In this talk, we show that the Gutzwiller-Jastrow wavefunctions are the eigen-states of the Hubbard model at U = +∞ at less than half-filling. The full energy spectrum and an infinite set of mutually commuting constants of motion are also given in this limit fo...
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The first “Convegno Informale su Quantum Groups” was held in Florence from February 3 to 6, 1993. This Convegno was conceived as an informal meeting to bring together all the italian people working in the field of quantum groups and related topics. We are very happy indeed that about 30 theoretical physicists decided to take part presenting many aspects of this interesting and live subject of r...
متن کاملExtended Hubbard model on a C20 molecule
The electronic correlations on a C20 molecule, as described by an extended Hubbard Hamiltonian with a nearest-neighbor Coulomb interaction of strength V , are studied using quantum Monte Carlo and exact diagonalization methods. For electron-doped C20, it is known that pair binding arising from a purely electronic mechanism is absent within the standard Hubbard model (V = 0). Here we show that t...
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ژورنال
عنوان ژورنال: Banach Center Publications
سال: 1997
ISSN: 0137-6934,1730-6299
DOI: 10.4064/-40-1-361-368