Electronic Properties of Single-Layer CoO$_2$/Au(111)

TL;DR

This study combines ARPES measurements and DFT+GA calculations to analyze the electronic structure of single-layer CoO$_2$ on Au(111), revealing it as a moderately correlated metal with substrate and hydroxylation effects.

Contribution

First combined ARPES and DFT+GA study of single-layer CoO$_2$, providing detailed insights into its electronic structure and substrate effects.

Findings

Fermi contour shows a large hole pocket at $ar{ ext{Γ}}$ point

Material identified as a moderately correlated metal

Substrate effects and hydroxylation influence electronic properties

Abstract

We report direct measurements via angle-resolved photoemission spectroscopy (ARPES) of the electronic dispersion of single-layer CoO$_2$. The Fermi contour consists of a large hole pocket centered at the $\overline{\Gamma}$ point. To interpret the ARPES results, we use density functional theory (DFT) in combination with the multi-orbital Gutzwiller Approximation (DFT+GA), basing our calculations on crystalline structure parameters derived from x-ray photoelectron diffraction and low-energy electron diffraction. Our calculations are in good agreement with the measured dispersion. We conclude that the material is a moderately correlated metal. We also discuss substrate effects, and the influence of hydroxylation on the CoO$_2$ single-layer electronic structure.