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arXiv · 1610.02998

Ab initio dynamical vertex approximation

Anna Galler·Patrik Thunström·Patrik Gunacker·Jan M. Tomczak·Karsten Held
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Abstract

Diagrammatic extensions of dynamical mean field theory (DMFT) such as the dynamical vertex approximation (D$Γ$A) allow us to include non-local correlations beyond DMFT on all length scales and proved their worth for model calculations. Here, we develop and implement an AbinitioD$Γ$A approach for electronic structure calculations of materials. Starting point is the two-particle irreducible vertex in the two particle-hole channels which is approximated by the bare non-local Coulomb interaction and all local vertex corrections. From this we calculate the full non-local vertex and the non-local self-energy through the Bethe-Salpeter equation. The AbinitioD$Γ$A approach naturally generates all local DMFT correlations and all non-local $GW$ contributions, but also further non-local correlations beyond: mixed terms of the former two and non-local spin fluctuations. We apply this new methodology to the prototypical correlated metal SrVO$_3$.

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Anna Galler, Patrik Thunström, Patrik Gunacker, Jan M. Tomczak, Karsten Held. 2017-02-16. Ab initio dynamical vertex approximation. https://doi.org/10.1103/physrevb.95.115107

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