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Mott-Hubbard insulators for systems with orbital degeneracy

Olle Gunnarsson·Erik Koch·Richard M. Martin
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Abstract

We study how the electron hopping reduces the Mott-Hubbard band gap in the limit of a large Coulomb interaction U and as a function of the orbital degeneracy N. The results support the conclusion that the hopping contribution grows as roughly \sqrt{N}W, where W is the one-particle band width, but in certain models a crossover to a \sim NW behavior is found for a sufficiently large N.

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Olle Gunnarsson, Erik Koch, Richard M. Martin. 1997-01-21. Mott-Hubbard insulators for systems with orbital degeneracy. https://doi.org/10.1103/physrevb.56.1146

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