Topological Quasi-2D Semimetal Co$_3$Sn$_2$S$_2$: Insights To Electronic Structure From NEXAFS and Resonant Photoelectron Spectroscopy

TL;DR

This study investigates the electronic structure of the topological semimetal Co$_3$Sn$_2$S$_2$ using NEXAFS and resonant photoelectron spectroscopy, revealing delocalized Co 3d electrons and providing insights relevant for technological applications.

Contribution

The paper provides the first detailed element- and orbital-specific electronic structure analysis of Co$_3$Sn$_2$S$_2$ using advanced spectroscopic techniques and first-principles calculations.

Findings

Observation of dominant Auger contribution indicating delocalized Co 3d electrons.

Element- and orbital-specific electronic states characterized near the Fermi level.

Insights into the electronic structure relevant for catalysis and water splitting applications.

Abstract

The electronic structure of the natural topological semimetal Co$_3$Sn$_2$S$_2$ crystals was studied using near-edge x-ray absorption spectroscopy (NEXAFS) and resonant photoelectron spectroscopy (ResPES). Although, the significant increase of the Co\,$3d$ valence band emission is observed at the Co\,$2p$ absorption edge in the ResPES experiments, the spectral weight at these photon energies is dominated by the normal Auger contribution. This observation indicates the delocalised character of photoexcited Co\,$3d$ electrons and is supported by the first-principle calculations. Our results on the investigations of the element- and orbital-specific electronic states near the Fermi level of Co$_3$Sn$_2$S$_2$ are of importance for the comprehensive description of the electronic structure of this materials, which is significant for future applications of this material in different areas of science and technology, including catalysis and water splitting applications.