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Effect of Hund's exchange on the spectral function of a triply orbital degenerate correlated metal

P. Lombardo·A. - M. Daré·R. Hayn
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Abstract

We present an approach based on the dynamical mean field theory which is able to give the excitation spectrum of a triply degenerate Hubbard model with a Hund's exchange invariant under spin rotation. The lattice problem can be mapped onto a local Anderson model containing 64 local eigenstates. This local problem is solved by a generalized non-crossing approximation. The influence of Hund's coupling J is examined in detail for metallic states close to the metal insulator transition. The band-filling is shown to play a crucial role concerning the effect of J on the low energy dynamics.

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P. Lombardo, A. - M. Daré, R. Hayn. 2005-11-15. Effect of Hund's exchange on the spectral function of a triply orbital degenerate correlated metal. https://doi.org/10.1103/physrevb.72.245115

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