Spectral Weight of Resonant Inelastic X-Ray Scattering in Doped Cuprates: Effect of Core-Hole Lifetime

TL;DR

This study investigates how the core-hole lifetime influences the spectral weight in RIXS experiments on doped cuprates, revealing differential sensitivities in spin-flip and non-spin-flip channels and the contributions of charge and magnon excitations.

Contribution

It provides a detailed analysis of the core-hole lifetime effects on RIXS spectral weight using exact diagonalization, highlighting the different behaviors in spin-flip and non-spin-flip channels.

Findings

Spin-flip channel less sensitive to core-hole lifetime.

Non-spin-flip channel spectral weight depends strongly on lifetime.

Charge and two-magnon excitations dominate at different lifetimes.

Abstract

We examine the effect of core-hole lifetime on the spectral weight of resonant inelastic x-ray scattering (RIXS) in hole-doped cuprates. We calculate the spectral weight by using exact diagonalization technique for a 4x4 doped Hubbard lattice and find that spin-flip channel detecting single-magnon excitation is less sensitive to the core-hole lifetime while in non-spin-flip channel the spectral weight is strongly dependent on the lifetime. In the latter, charge and two-magnon excitations predominately contribute to RIXS for short and long core-hole lifetimes, respectively. For a realistic value of the core-hole lifetime in cuprates, both the charge and two-magnon excitations are expected to contribute to non-spin-flip channel in RIXS when the incident-photon energy is tuned to the main peak of x-ray absorption spectrum.