2024/10/25 by Viktor Christiansson, Christiansson, Viktor, Francesco Petocchi +3
Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Strongly Correlated Electrons (cond-mat.str-el) #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.48550/arxiv.2410.19579
published as Phys. Rev. B 114, 065123 (2026)
arxiv created 2026/07/29 · arxiv updated 2026/07/30
Theoretical studies of semiconductors and band insulators are usually based on variants of the GW method without full self-consistency, like single-shot G0W0 or quasiparticle self-consistent GW. Fully self-consistent GW provides a poor description of the gap size and electronic structure due to the lack of vertex corrections. While it is hard to predict at which order corrections can be neglected, local vertex corrections to all orders can be consistently included by combining GW with extended dynamical mean field theory (EDMFT). Here, we show that ab initio multitier GW+EDMFT calculations, which achieve full self-consistency in a suitably defined low-energy space, provide an accurate description of semiconductors and band insulators, comparable to the established methods which are typically used for this class of materials. Our results demonstrate that the range of applicability of GW+EDMFT extends to weakly correlated systems, and they imply that despite the weak correlations, local vertex corrections are an important ingredient in the diagrammatic treatment of semiconductors and band insulators.