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Gutzwiller Approximation in Degenerate Hubbard Models

Jian Ping Lu
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Abstract

Degenerate Hubbard models are studied using the Generalized-Gutzwiller-Approximation. It is found that the metal-insulator transition occurs at a finite correlation $U_c$ when the average number of electrons per lattice site is an integer. The critical $U_c$ depends sensitively on both the band degeneracy $N$ and the filling $x$. A derivation is presented for the general expression of $U_c(x,N)$ which reproduces all previously known Gutzwiller solutions, including that of the Boson Hubbard model. Effects of the lattice structure on the metal-insulator transition and the effective mass are discussed.

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Jian Ping Lu. 1996-01-27. Gutzwiller Approximation in Degenerate Hubbard Models. https://doi.org/10.1142/s0217979296002026

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