Monovacancy and Substitutional Defects in Hexagonal Silicon Nanotubes

TL;DR

This study uses first-principles calculations to analyze how monovacancies and substitutional impurities like C, Al, or P affect the structure and electronic properties of hexagonal silicon nanotubes, revealing defect-induced local states.

Contribution

It provides a detailed first-principles analysis of defect-induced structural deformation and electronic states in hexagonal silicon nanotubes, highlighting impurity-specific effects.

Findings

Defects cause deformation of silicon nanotubes.

Localized unoccupied states near the Fermi level are induced by defects.

Different impurities lead to distinct geometrical and electronic properties.

Abstract

We present a first-principle study of geometrical and electronic structure of hexagonal single-walled silicon nanotubes with a monovacancy or a substitutional defect. The C, Al or P atoms are chosen as substitutional impurities. It is found that the defect such as a monovacancy or a substitutional impurity results in deformation of the hexagonal single-walled silicon nanotube. In both cases, a relatively localized unoccupied state near the Fermi level occurs due to this local deformation. The difference in geometrical and electronic properties of different substitutional impurities is discussed.