GW method applied to localized 4f electron systems

TL;DR

This paper demonstrates that the quasiparticle self-consistent GW (QSGW) method effectively models localized 4f electron systems, accurately reproducing experimental data and predicting critical electronic phase transitions.

Contribution

The study applies QSGW to various 4f systems, showing it combines advantages of GW and LDA+U methods in an ab initio framework.

Findings

QSGW accurately reproduces occupied 4f levels

Fermi surface properties agree with experiments

GdN is near a metal-insulator transition point

Abstract

We apply a recently developed quasiparticle self-consistent $GW$ method (QSGW) to Gd, Er, EuN, GdN, ErAs, YbN and GdAs. We show that QSGW combines advantages separately found in conventional $GW$ and LDA+$U$ theory, in a simple and fully \emph{ab initio} way. \qsgw reproduces the experimental occupied $4f$ levels well, though unoccupied levels are systematically overestimated. Properties of the Fermi surface responsible for electronic properties are in good agreement with available experimental data. GdN is predicted to be very near a critical point of a first-order metal-insulator transition.