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Many-Body Approximation Scheme Beyond GW

Ping Sun·Gabriel Kotliar
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Abstract

We explore the combination of the extended dynamical mean field theory (EDMFT) with the GW approximation (GWA); the former sums the local contributions to the self-energies to infinite order in closed form and the latter handles the non-local ones to lowest order. We investigate the different levels of self-consistency that can be implemented within this method by comparing to the exact QMC solution of a finite-size model Hamiltonian. We find that using the EDMFT solution for the local self-energies as input to the GWA for the non-local self-energies gives the best result.

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Ping Sun, Gabriel Kotliar. 2004-05-13. Many-Body Approximation Scheme Beyond GW. https://doi.org/10.1103/physrevlett.92.196402

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