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Strong-Coupling Perturbation Theory of the Hubbard Model

Stephane Pairault·David Senechal·A. -M. S. Tremblay
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Abstract

The strong-coupling perturbation theory of the Hubbard model is presented and carried out to order (t/U)^5 for the one-particle Green function in arbitrary dimension. The spectral weight A(k,omega) 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 antiferromagnet) are identified in the temperature--hopping integral (T,t) plane. This work completes a first paper on the subject (Phys. Rev. Lett. 80, 5389 (1998)) by providing details on diagrammatic rules and higher-order results. In addition, the non half-filled case, infinite resummations of diagrams and the double occupancy are discussed. Various tests of the method are also presented.

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Stephane Pairault, David Senechal, A. -M. S. Tremblay. 1999-05-17. Strong-Coupling Perturbation Theory of the Hubbard Model. https://doi.org/10.1007/s100510070253

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