Controlling edge states of zigzag carbon nanotubes by the Aharonov-Bohm flux

TL;DR

This paper demonstrates that the Aharonov-Bohm flux can control localized edge states in zigzag carbon nanotubes, with potential implications for understanding curvature effects and conductance properties.

Contribution

It reveals how the Aharonov-Bohm flux influences localized edge states and their localization length in zigzag carbon nanotubes, highlighting a new control mechanism.

Findings

Localized states exist around zigzag edges with energies between bands.

The localization length of critical states is sensitive to curvature and magnetic flux.

Weak magnetic fields can close the curvature-induced mini-gap.

Abstract

It has been known theoretically that localized states exist around zigzag edges of a graphite ribbon and of a carbon nanotube, whose energy eigenvalues are located between conduction and valence bands. We found that in metallic single-walled zigzag carbon nanotubes two of the localized states become critical, and that their localization length is sensitive to the mean curvature of a tube and can be controlled by the Aharonov-Bohm flux. The curvature induced mini-gap closes by the relatively weak magnetic field. Conductance measurement in the presence of the Aharonov-Bohm flux can give information about the curvature effect and the critical states.