Dynamical cluster approximation within an augmented plane-wave framework: Spectral properties of SrVO$_3$

TL;DR

This paper introduces an LDA+DCA method within a full-potential linear augmented plane-wave framework to study spectral properties of SrVO$_3$, showing improved agreement with experimental ARPES data over previous LDA+DMFT results.

Contribution

The paper develops and applies a combined LDA+DCA approach within a full-potential LAPW method, capturing both local and spatial quantum fluctuations in correlated materials.

Findings

Qualitative agreement with ARPES spectra.

More pronounced coherent peaks below Fermi level.

Resolution of spectral functions showing coexistence of insulating and metallic phases.

Abstract

We present a combination of local density approximation (LDA) with the dynamical cluster approximation (LDA+DCA) in the framework of the full-potential linear augmented plane-wave method, and compare our LDA+DCA results for SrVO$_3$ to LDA with the dynamical mean field theory (LDA+DMFT) calculations as well as experimental observations on SrVO$_3$. We find a qualitative agreement of the momentum resolved spectral function with angle-resolved photoemission spectra (ARPES) and former LDA+DMFT results. As a correction to LDA+DMFT, we observe more pronounced coherent peaks below the Fermi level, as indicated by ARPES experiments. In addition, we resolve the spectral functions in the ${\bf K}_{0}=(0,0,0)$ and ${\bf K}_{1}=(\pi,\pi,\pi)$ sectors of DCA, where band insulating and metallic phases coexist. Our approach can be applied to correlated compounds where not only local quantum fluctuations but also spatial fluctuations are important.