Momentum dependence in K-edge resonant inelastic x-ray scattering and its application to screening dynamics in CE-phase La$_{0.5}$Sr$_{1.5}$MnO$_4$

TL;DR

This paper develops a formula for K-edge resonant inelastic x-ray scattering that includes momentum dependence and applies it to a manganite, revealing localized screening and demonstrating the technique's utility in probing screening dynamics.

Contribution

The paper introduces an extended formula for K-edge RIXS with momentum dependence and multiple core-hole sites, applied to a complex manganite.

Findings

Good agreement with experimental RIXS data

Screening in La0.5Sr1.5MnO4 is highly localized

K-edge RIXS can probe screening dynamics

Abstract

We present a formula for the calculation of K-edge resonant inelastic x-ray scattering on transition metal compounds, based on a local interaction between the valence shell electrons and the $1s$ core hole. Extending a previous result, we include explicit momentum dependence and a basis with multiple core-hole sites. We apply this formula to a single-layered charge, orbital and spin ordered manganite, La$_{0.5}$Sr$_{1.5}$MnO$_4$, and obtain good agreement with experimental data, in particular with regards to the large variation of the intensity with momentum. We find that the screening in La$_{0.5}$Sr$_{1.5}$MnO$_4$ is highly localized around the core-hole site and demonstrate the potential of K-edge resonant inelastic x-ray scattering as a probe of screening dynamics in materials.