An Investigation of Particle-Hole Asymmetry in the Cuprates via Electronic Raman Scattering

TL;DR

This study uses quantum Monte Carlo simulations of the Hubbard model to analyze electron-hole asymmetry in the Raman spectra of cuprates, comparing theoretical results with experimental data.

Contribution

It demonstrates that the Hubbard model with a fixed interaction strength can qualitatively reproduce doping and temperature effects in Raman spectra of cuprates, highlighting the role of strong correlations.

Findings

Hubbard model captures doping dependence of Raman spectra

Electron-hole asymmetry explained by strong correlations

Fixed interaction strength suffices for qualitative agreement

Abstract

In this paper we examine the effects of electron-hole asymmetry as a consequence of strong correlations on the electronic Raman scattering in the normal state of copper oxide high temperature superconductors. Using determinant quantum Monte Carlo simulations of the single-band Hubbard model, we construct the electronic Raman response from single particle Green's functions and explore the differences in the spectra for electron and hole doping away from half filling. The theoretical results are compared to new and existing Raman scattering experiments on hole-doped La$_{2-x}$Sr$_{x}$CuO$_{4}$ and electron-doped Nd$_{2-x}$Ce$_{x}$CuO$_{4}$. These findings suggest that the Hubbard model with fixed interaction strength qualitatively captures the doping and temperature dependence of the Raman spectra for both electron and hole doped systems, indicating that the Hubbard parameter U does not need to be doping dependent to capture the essence of this asymmetry.