[Zurück]

K. Held:
"Dynamical vertex approximation - electronic correlations beyond DMFT";
Vortrag: What about U? - Corrective approaches to DFT for strongly-correlated systems., Lausanne, Schweiz (eingeladen); 19.06.2012 - 21.06.2012.

Dynamical mean field theory includes a major part of the electronic correlations: the local ones for two f- or d-electrons on the same lattice site. Often however interesting correlation physics emerges from non local correlations such as e.g. (quantum) criticality and d-wave superconductivity. I will discuss our recent efforts to include these non-local correlations diagrammatically in the dynamical vertex approximation [1]. This allows among others to calculate critical exponents [2] and to open a pseudogap in the spectrum. The dynamical vertex approximation is also appropriate for going beyond GW or GW+DMFT [3], on the basis of Hedin's equations.