All-electron many-body approach to resonant inelastic x-ray scattering

TL;DR

This paper develops a comprehensive all-electron many-body formalism for calculating resonant inelastic x-ray scattering (RIXS) spectra, emphasizing the role of electron-hole interactions and atomic coherence.

Contribution

It introduces a new formalism for RIXS cross section calculation within an all-electron many-body perturbation theory framework, implemented in the exciting package.

Findings

Electron-hole correlation significantly affects RIXS spectra.

Atomic coherence plays a crucial role in spectral features.

Method successfully applied to diamond and $eta$-Ga$_2$O$_3$.

Abstract

We present a formalism for the resonant inelastic x-ray scattering (RIXS) cross section. The resulting compact expression in terms of polarizability matrix elements, particularly lends itself to the implementation in an all-electron many-body perturbation theory (MBPT) framework, which is realized in the full-potential package exciting. With the carbon K edge RIXS of diamond and the oxygen K edge RIXS of $\beta-\mathrm{Ga_2 O_3}$, respectively, we demonstrate the importance of electron-hole correlation and atomic coherence in the RIXS spectra.