Single particle spectra of charge transfer insulators by cluster perturbation theory - the correlated band structure of NiO

TL;DR

This paper introduces a computationally efficient many-body method for calculating the band structure of strongly correlated materials, successfully applied to NiO with results matching experimental data.

Contribution

It develops a translationally invariant cluster perturbation theory approach that accurately captures the correlated band structure of NiO.

Findings

Good agreement between calculated and experimental spectral functions.

Method is computationally comparable to standard band structure calculations.

Effective treatment of Coulomb interactions within d-shells.

Abstract

We propose a many-body method for band-structure calculations in strongly correlated electron systems and apply it to NiO. The method may be viewed as a translationally invariant version of the cluster method of Fujimori and Minami. Thereby the Coulomb interaction within the d-shells is treated by exact diagonalization and the d-shells then are coupled to a solid by an extension of the cluster perturbation theory due to Senechal et al. The method is computationally no more demanding than a conventional band structure calculation and for NiO we find good agreement between the calculated single particle spectral function and the experimentally measured band structure.