LDA+DMFT approach to resonant inelastic x-ray scattering in correlated materials

TL;DR

This paper introduces an ab initio LDA+DMFT computational method to accurately simulate RIXS spectra in correlated 3d transition-metal oxides, capturing complex excitations with minimal empirical parameters.

Contribution

It extends the cluster model by incorporating unbound electron-hole pairs and charge-transfer excitations within a DMFT framework, improving the theoretical description of RIXS.

Findings

Good agreement with experimental RIXS data

Clarifies the link between correlated bands and fluorescence features

Provides a less empirical, more material-specific modeling approach

Abstract

We present a computational study of $L$-edge resonant inelastic x-ray scattering (RIXS) in correlated 3$d$ transition-metal oxides using an $ab$ $initio$ method based on local density approximation + dynamical mean-field theory (DMFT). The present method, building on Anderson impurity model with an optimized continuum bath within DMFT, is an extension of the cluster model to include unbound electron-hole pair excitations as well as material-specific charge-transfer excitations with less empirical parameters. We find a good agreement with available experimental data. The relationship between correlated bands and fluorescence-like feature in the RIXS spectra is discussed.