Concentration-Diversified Magnetic and Electronic Properties of Halogen-Adsorbed Silicene

TL;DR

This study uses first-principles calculations to explore how halogen adsorption affects the magnetic and electronic properties of silicene, revealing diverse behaviors depending on adsorption configuration and concentration.

Contribution

It provides a comprehensive theoretical analysis of halogen-adsorbed silicene's electronic structures, highlighting differences between single-side and double-side adsorption effects.

Findings

Double-side adsorption leads to finite gap semiconductors or p-type metals.

Single-side adsorption results in valence bands with/without spin-splitting.

Characteristic halogen-related bands are identified at various energies.

Abstract

Diverse magnetic and electronic properties of halogen-adsorbed silicene are investigated by the first-principles theoretical framework, including the adatom-diversified geometric structures, the atom-dominated energy bands, the spatial spin density distributions, the spatial charge density distributions and its variations, and the spin- and orbital-projected density of states. Also, such physical quantities are sufficient to identify similar and different features in the double-side and single-side adsorptions. The former belongs to the concentration-depended finite gap semiconductors or p-type metals, while the latter display the valence energy bands with/without spin-splitting intersecting with the Fermi level. Both adsorption types show the halogen-related weakly dispersed bands at deep energies, the adatom-modified middle-energy sigma bands, and the recovery of low-energy pi bands during the destruction of the halogen concentrations. Such feature-rich band structures can be verified by the angle-resolved photoemission spectroscopy experiment.