منابع مشابه
Strong-coupling perturbation theory of the Hubbard model
The strong-coupling perturbation theory of the Hubbard model is presented and carried out to order (t/U) for the one-particle Green function in arbitrary dimension. The spectral weight A(k, ω) is expressed as a Jacobi continued fraction and compared with new Monte-Carlo data of the one-dimensional, half-filled Hubbard model. Different regimes (insulator, conductor and short-range antiferromagne...
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We develop a strong-coupling perturbation theory for the extended Bose-Hubbard model with on-site and nearest-neighbor boson-boson repulsions on d 1 -dimensional hypercubic lattices. Analytical expressions for the ground-state phase boundaries between the incompressible Mott or charge-density-wave insulators and the compressible superfluid or supersolid phases are derived up to third order in t...
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We study the strong-coupling regime of the t-t8 Hubbard model, filled up to the level of the van Hove singularities, by means of an exact diagonalization approach. We characterize the different phases of the model by the different sectors of the Hilbert space with given quantum numbers. By looking for the ground state of the system, we find essentially the competition between a state with incip...
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We extend the analysis of the renormalization group flow in the two-dimensional Hubbard model close to half-filling using the recently developed temperature flow formalism. We investigate the interplay of d-density wave and Fermi surface deformation tendencies with those towards d-wave pairing and antiferromagnetism. For a ratio of next nearest to nearest neighbor hoppings, t′/t = −0.25, and ba...
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ژورنال
عنوان ژورنال: Journal of Physics A: Mathematical and General
سال: 2006
ISSN: 0305-4470,1361-6447
DOI: 10.1088/0305-4470/39/41/s16