An ab initio design of cluster-assembled silicon nanotubes

TL;DR

This study uses density functional calculations to design silicon nanotubes assembled from silicon clusters, revealing their tunable electronic properties and potential applications in spintronics through transition metal doping.

Contribution

It introduces a method to design silicon nanotubes from silicon clusters and explores their electronic tuning via transition metal doping, especially Fe.

Findings

SiNTs can be semiconductors with large band gaps.

Fe doping induces metallic and magnetic properties.

Increasing tube radius causes a metal to half-metal transition.

Abstract

Density functional calculations were performed to systematically study a series of finite and infinite cluster-assembled silicon nanotubes (SiNTs). One-dimensional SiNTs can be prepared by proper assembly of hydrogenated cage-like silicon clusters to form semiconductors with a large band gap, and their electronic properties can be accurately tuned by transition metal doping in the center of the tubes. Specifically, doping with Fe made the SiNTs metallic and magnetic materials. More interestingly, a metal to half-metal transition was observed with increasing tube radius in Fe-doped SiNTs, which demonstrates that SiNTs doped with magnetic elements may find important applications in spintronics.