Real Space Green's Function Approach to RIXS

TL;DR

This paper introduces an ab initio real-space Green's function method for modeling RIXS spectra, incorporating many-body effects and providing qualitative agreement with experimental data.

Contribution

It develops a novel real-space Green's function approach for RIXS that includes many-body corrections and simulates lifetime-broadening effects.

Findings

Qualitative agreement with experimental RIXS data

Simulation of lifetime-broadening suppressed XAS

Effective convolution model for RIXS spectrum

Abstract

We present an ab initio theory of core- and valence resonant inelastic x-ray scattering (RIXS) based on a real-space multiple scattering Green's function formalism and a quasi-boson model Hamiltonian. Simplifying assumptions are made which lead to an approximation of the RIXS spectrum in terms of a convolution of an effective x-ray absorption signal with the x-ray emission signal. Additional many body corrections are incorporated in terms of an effective energy dependent spectral function. Example calculations of RIXS are found to give qualitative agreement with experimental data. Our approach also yields simulations of lifetime-broadening suppressed XAS, as observed in high energy resolutionfluorescence detection experiment (HERFD). Finally possible improvements to our approach are briefly discussed.