Direct observation of band-gap closure for a semiconducting carbon nanotube in a large parallel magnetic field

TL;DR

This study experimentally observes the magnetic field-induced closure and reopening of the band gap in semiconducting carbon nanotubes, revealing the effects of high magnetic fields and mechanical strain on their electronic properties.

Contribution

First direct experimental observation of band-gap closure and reopening in semiconducting CNTs under high magnetic fields, including strain effects.

Findings

Band-gap closure observed at high magnetic fields

Reopening of the band gap with varying magnetic field

Mechanical strain significantly influences magnetoconductance

Abstract

We have investigated the magnetoconductance of semiconducting carbon nanotubes (CNTs) in pulsed, parallel magnetic fields up to 60 T, and report the direct observation of the predicted band-gap closure and the reopening of the gap under variation of the applied magnetic field. We also highlight the important influence of mechanical strain on the magnetoconductance of the CNTs.