Quasiparticle bandstructure effects on the {\it d} hole lifetimes of copper within the GW approximation

TL;DR

This study uses first-principles GW calculations to analyze d-hole lifetimes in copper, revealing that non-self-consistent approaches align better with experiments due to specific decay channels.

Contribution

It demonstrates that G0W0 calculations accurately predict copper d-hole lifetimes by capturing decay channels that are lost at higher self-consistency levels.

Findings

G0W0 results agree with experimental lifetimes

Self-consistency worsens lifetime predictions

Intraband decay channels are crucial for accurate lifetimes

Abstract

We investigate the lifetime of {\it d} holes in copper within a {\it first--principle} $GW$ approximation. At the $G_0W_0$ level the lifetime of the topmost {\it d} bands are in agreement with the experimental results and are four times smaller than those obtained in the ``on--shell'' calculations commonly used in literature. The theoretical lifetimes and bandstructure, however, worsen when further iterative steps of self-consistency are included in the calculation, pointing to a delicate interplay between self--consistency and the inclusion of vertex corrections. We show that the $G_0W_0$ success in the lifetimes calculation is due to the opening of new ``intraband'' decay channels that disappear at self--consistency.