Comparative study of correlation effects in CaVO3 and SrVO3

TL;DR

This study uses advanced computational methods to compare the electronic correlation effects in two similar transition metal oxides, revealing subtle differences that align with recent experimental findings.

Contribution

It provides a parameter-free LDA+DMFT analysis showing that CaVO3 and SrVO3 are strongly correlated metals with similar low-energy spectra despite structural differences.

Findings

Both materials are strongly correlated metals.

Their low-energy spectra are nearly identical.

Differences appear mainly at energies above the Fermi level.

Abstract

We present parameter-free LDA+DMFT (local density approximation + dynamical mean field theory) results for the many-body spectra of cubic SrVO3 and orthorhombic CaVO3. Both systems are found to be strongly correlated metals, but not on the verge of a metal-insulator transition. In spite of the considerably smaller V-O-V bond angle in CaVO3 the LDA+DMFT spectra of the two systems for energies E<E_F are very similar, their quasiparticle parts being almost identical. The calculated spectrum for E>E_F shows more pronounced, albeit still small, differences. This is in contrast to earlier theoretical and experimental conclusions, but in good agreement with recent bulk-sensitive photoemission and x-ray absorption experiments.