Probing Magnetic Gap Collapse within a Three-band Model of Resonant inelastic x-ray scattering (RIXS) in the Cuprates

TL;DR

This paper models the magnetic gap collapse in cuprates using a three-band Hubbard Hamiltonian and compares theoretical RIXS spectra with experimental data, revealing doping-dependent spectral changes.

Contribution

It introduces a three-band Hubbard model to analyze RIXS spectra and identifies signatures of magnetic gap collapse in doped cuprates.

Findings

RIXS spectra show gap collapse signatures with doping.

Electron-doped cuprates support the gap collapse scenario.

Hole-doped cuprates exhibit less clear spectral signatures.

Abstract

We present a three-band Hubbard Hamiltonian and the associated Cu K-edge RIXS spectra for electron and hole doped cuprates over a wide range of energy and momentum transfers. By comparing computed spectra for the unfilled case with the corresponding results for 15% electron or hole doping at two different values of the effective Hubbard parameter U, generic signatures of the collapse of the magnetic gap and the characteristic momentum dependencies and evolution of the spectra with doping are identified. Available RIXS data support the gap collapse scenario for electron doped cuprates, but the situation in hole doped systems is found to be less clear.