Abstract
The electronic structure of layered van der Waals ferromagnet is studied with self-consistent diagrammatic approaches beyond GW approximation. Considerable improvement in the calculated band gap as compared to the non-self-consistent results has been found. Certain spectral features in the valence bands discovered recently by angle-resolved photoemission spectroscopy are reproduced better when we use full frequency-dependent self-energy. Density-functional theory and quasiparticle self-consistent GW method which are based on frequency-independent self-energy are unable to resolve these features. Nonlocality effects in the diagrams beyond GW approximation are large for both polarizability and self-energy. This finding can potentially have an impact on the development of methods like GWdynamical mean field theory.
5 More- Received 17 May 2021
- Accepted 16 August 2021
DOI:https://doi.org/10.1103/PhysRevMaterials.5.083805
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