Abstract
The self-consistent method satisfies the Ward-Takahashi identity (i.e., the gauge invariance or the local charge continuity) for arbitrary energy () and momentum () transfers. Its self-consistent first-principles treatment of the vertex or is possible to first order in the bare () or dynamically screened () Coulomb interaction. It is developed within a linearized scheme and combined with the Bethe-Salpeter equation (BSE) to accurately calculate photoabsorption spectra (PAS) and photoemission (or inverse photoemission) spectra (PES) simultaneously. The method greatly improves the PAS of Na, , and calculated using the standard one-shot method that results in significantly redshifted PAS by 0.8–3.1 eV, although the PES are well reproduced already in .
- Received 30 July 2015
- Revised 29 June 2016
DOI:https://doi.org/10.1103/PhysRevB.94.121116
©2016 American Physical Society