Mott Gap Excitations and Resonant Inelastic X-Ray Scattering in Doped Cuprates

TL;DR

This paper predicts how doping affects the Mott gap in high-Tc cuprates, using numerical simulations of the Hubbard model to interpret RIXS measurements and highlight the role of charge interactions and magnetic correlations.

Contribution

It provides new theoretical predictions for the doping and momentum dependence of Mott gap excitations observed in RIXS in cuprates.

Findings

Mott gap excitations are influenced by doping and momentum.

Charge carriers interact with antiferromagnetic correlations.

Particle-hole asymmetry affects Mott gap behavior.

Abstract

Predictions are made for the momentum- and carrier-dependent degradation of the Mott gap upon doping in high-Tc cuprates as would be observed in Cu K-edge resonant inelastic x-ray scattering (RIXS). The two-dimensional Hubbard model with second- and third-nearest-neighbor hopping terms has been studied by numerical exact diagonalization. Special emphasis is placed on the particle-hole asymmetry of the Mott gap excitations. We argue that the Mott gap excitations observed by RIXS are significantly influenced by the interaction between charge carriers and antiferromagnetic correlations.