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Dynamical vertex approximation - a step beyond dynamical mean field theory

A. Toschi·A. A. Katanin·K. Held
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Abstract

We develop a diagrammatic approach with local and nonlocal self-energy diagrams, constructed from the local irreducible vertex. This approach includes the local correlations of dynamical mean field theory and long-range correlations beyond. It allows for example to describe (para-)magnons and weak localization effects in strongly correlated systems. As a first application, we study the interplay between nonlocal antiferromagnetic correlations and the strong local correlations emerging in the vicinity of a Mott-Hubbard transition.

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A. Toschi, A. A. Katanin, K. Held. 2007-06-01. Dynamical vertex approximation - a step beyond dynamical mean field theory. https://doi.org/10.1103/physrevb.75.045118

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