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

Duy Khanh Nguyen,Ming-Fa Lin,Ngoc Thanh Thuy Tran,Yu-Huang Chiu

doi:10.1038/s41598-019-50233-w

Abstract

Diverse magnetic and electronic properties of halogen-adsorbed silicene are investigated by the first-principle theoretical framework, including the adatom-diversified geometric structures, atom-dominated energy bands, spatial spin density distributions, spatial charge density distributions and its variations, 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 σ bands, and the recovery of low-energy π bands during the decrease of the halogen concentrations. Such feature-rich band structures can be verified by the angle-resolved photoemission spectroscopy experiment.

Highlights

A new era of material sciences has arisen since the successful fabrication of two-dimensional (2D) graphene[1,2]
The double-side [Fig. 1(a)] and single-side [Fig. 1(b)] adsorptions are considered in calculations to evidence that these adsorption types can present the diverse magnetic and electronic properties, in which they are determined by the adatom-diversified geometric structures, atom-dominated energy bands, the spatial spin density distributions, the spatial charge density distributions and its difference, and the orbital-projected density of states (DOSs)
The predicted results in the geometric structures, band structures, and DOSs can be verified by the scanning tunneling microscopy (STM), angle-resolved photoemission spectroscopy (ARPES), and scanning tunneling spectroscopy (STS) experiments, respectively

Summary

Introduction

A new era of material sciences has arisen since the successful fabrication of two-dimensional (2D) graphene[1,2]. The double-side [Fig. 1(a)] and single-side [Fig. 1(b)] adsorptions are considered in calculations to evidence that these adsorption types can present the diverse magnetic and electronic properties, in which they are determined by the adatom-diversified geometric structures, atom-dominated energy bands, the spatial spin density distributions, the spatial charge density distributions and its difference, and the orbital-projected density of states (DOSs) Via such physical quantities, the similar and different characteristics in double-side and single-side adsorption cases are thoroughly identified, including the halogen-related weakly dispersed bands at deep energies, the adatom-modified middle-energy σ bands, the recovery of low-energy π bands during the decrease of the halogen concentrations; the breaking of the mirror symmetry in the single-side adsorptions leads to the critical discrepancy, i.e., there appear the valence energy bands with/without spin-splitting intersecting with the Fermi level as a result of p-type metallic behavior. The predicted results in the geometric structures, band structures, and DOSs can be verified by the scanning tunneling microscopy (STM), angle-resolved photoemission spectroscopy (ARPES), and scanning tunneling spectroscopy (STS) experiments, respectively

Methods

Findings

Discussion

Conclusion