Momentum Dependence of Resonant Inelastic X-Ray Scattering Spectrum in Insulating Cuprates

TL;DR

This study investigates how the resonant inelastic x-ray scattering spectrum in insulating cuprates depends on momentum, revealing anisotropic features related to the upper Hubbard band using exact diagonalization.

Contribution

The paper introduces a detailed analysis of momentum dependence in RIXS spectra of cuprates using the Hubbard model with extended hopping terms, highlighting anisotropic features.

Findings

Unoccupied upper Hubbard band features can be extracted from RIXS spectra.

The spectrum shows anisotropic momentum dependence near Cu K edges.

Results aid understanding of doping effects in superconductors.

Abstract

The resonant inelastic x-ray scattering spectrum in insulating cuprates is examined by using the exact diagonalization technique on small clusters in the two-dimensional Hubbard model with second and third neighbor hopping terms. When the incident photon energy is tuned near the Cu K absorption edges, we find that the features of the unoccupied upper Hubbard band can be extracted from the spectrum through an anisotropic momentum dependence. They provide an opportunity for the understanding of the different behavior of hole- and electron-doped superconductors.