Many-body approximation scheme beyond GW.
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 nonlocal ones to lowest order. We investigate the different levels of self-consistency that can be implemented within this method by comparing to the exact quantum Monte Carlo 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 nonlocal self-energies gives the best result.
Sun
Ping
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Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA.
Kotliar
Gabriel
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