Multiple Localized States and Magnetic Orderings in Partially Open Zigzag Carbon Nanotube Superlattices: An Ab Initio Study

TL;DR

This study uses first-principles calculations to explore how partially open zigzag carbon nanotube superlattices exhibit localized electronic states and magnetic orderings, enabling potential nanoscale electronic and spintronic applications.

Contribution

It demonstrates the emergence of multiple localized states and magnetic orderings in partially open zigzag CNT superlattices, and shows their tunability via external electric fields and bias voltages.

Findings

Localized states around the Fermi energy depend on opening degree.

Some states exhibit special magnetic orderings.

Superlattices can act as giant magnetoresistive devices.

Abstract

Using first-principles calculations, we examine the electronic and magnetic properties of partially open zigzag carbon nanotube (CNT) superlattices. It is found that depending on their opening degree, these superlattices can exhibit multiple localized states around the Fermi energy. More importantly, some electronic states confined in some parts of the structure even have special magnetic orderings. We demonstrate that, as a proof of principle, some partially open zigzag CNT superlattices are by themselves giant (100%) magnetoresistive devices. Furthermore, the localized(and spin-polarized) states as well as the band gaps of the superlattices could be further modulated by external electric fields perpendicular to the tube axis, and a bias voltage along the tube axis may be used to control the conductance of two spin states. We believe that these results will open the way to the production of novel nanoscale electronic and spintronic devices.