Dynamical Vertex Approximation

Karsten Held

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arXiv · 1411.5191

Dynamical Vertex Approximation

Karsten Held

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Abstract

Dynamical vertex approximation is a Feynman diagrammatic extension of dynamical mean field theory, including non-local correlations on all time and length scales. Starting with the Dyson and the parquet equations, the lecture notes give an elementary introduction to the dynamical vertex approximation. As a benchmark, results for an exactly solvable benzene Hubbard ring are presented. Recent highlights, the calculation of the critical exponents of the Hubbard model in 3D and that long-range antiferromagnetic correlations in 2D actually shift the (paramagnetic) Mott transition to interaction U=0, are reviewed.

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Karsten Held. 2014-11-19. Dynamical Vertex Approximation. https://arxiv.org/abs/1411.5191

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