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One-Particle Excitation of the Two-Dimensional Hubbard Model

Ken Yokoyama·Hidetoshi Fukuyama
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Abstract

The real part of the self-energy of interacting two-dimensional electrons has been calculated in the t-matrix approximation. It is shown that the forward scattering results in an anomalous term leading to the vanishing renormalization factor of the one-particle Green function, which is a non-perturbative effect of the interaction U. The present result is a microscopic demonstration of the claim by Anderson based on the conventional many-body theory. The effect of the damping of the interacting electrons, which has been ignored in reaching above conclusion, has been briefly discussed.

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Ken Yokoyama, Hidetoshi Fukuyama. 1997-02-21. One-Particle Excitation of the Two-Dimensional Hubbard Model. https://doi.org/10.1143/jpsj.66.529

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