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Landau-Gutzwiller quasi-particles

J. Buenemann·F. Gebhard·R. Thul
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Abstract

We define Landau quasi-particles within the Gutzwiller variational theory, and derive their dispersion relation for general multi-band Hubbard models in the limit of large spatial dimensions D. Thereby we reproduce our previous calculations which were based on a phenomenological effective single-particle Hamiltonian. For the one-band Hubbard model we calculate the first-order corrections in 1/D and find that the corrections to the quasi-particle dispersions are small in three dimensions. They may be largely absorbed in a rescaling of the total band width, unless the system is close to half band filling. Therefore, the Gutzwiller theory in the limit of large dimensions provides quasi-particle bands which are suitable for a comparison with real, three-dimensional Fermi liquids.

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J. Buenemann, F. Gebhard, R. Thul. 2003-02-13. Landau-Gutzwiller quasi-particles. https://doi.org/10.1103/physrevb.67.075103

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