Valence band electronic structure of V2O3: identification of V and O bands

TL;DR

This study investigates the valence band electronic structure of V2O3 using photon energy-dependent photoemission and GW calculations, identifying orbital contributions and emphasizing the importance of bulk sensitivity for quasiparticle detection.

Contribution

It provides a detailed orbital analysis of V2O3's valence band across a wide photon energy range, combining experimental data with theoretical calculations.

Findings

V 4s located at about 8 eV binding energy

Quasiparticle peak intensity is not correlated with O 2p and V 3d yield variations

Bulk sensitivity is crucial for detecting low-energy excitations

Abstract

We present a comprehensive study of the photon energy dependence of the valence band photoemission yield in the prototype Mott-Hubbard oxide V2O3. The analysis of our experimental results, covering an extended photon energy range (20-6000 eV) and combined with GW calculations, allow us to identify the nature of the orbitals contributing to the total spectral weight at different binding energies, and in particular to locate the V 4s at about 8 eV binding energy. From this comparative analysis we can conclude that the intensity of the quasiparticle photoemission peak, observed close to the Fermi level in the paramagnetic metallic phase upon increasing photon energy, does not have a significant correlation with the intensity variation of the O 2p and V 3d yield, thus confirming that bulk sensitivity is an essential requirement for the detection of this coherent low energy excitation.