# Bandgap modulation of narrow-gap carbon nanotubes in a transverse electric field

Authors
Type
Published Article
Publication Date
Feb 02, 2006
Submission Date
Oct 18, 2005
Identifiers
DOI: 10.1209/epl/i2005-10446-x
arXiv ID: cond-mat/0510480
Source
arXiv
We propose a method to modulate the bandgaps in quasi-metallic carbon nanotubes using a transverse electric field. Unlike previous investigations, we include curvature effects of the nanotubes by incorporating both $\pi$- and $\sigma$-orbitals in our tight-binding calculations. The calculations show that the small curvature-induced bandgaps decrease quadratically with electric field amplitude to zero. As the electric field amplitude continues to increase, the bandgap then expands in a similar manner to that presented in earlier studies. The bandgap dependence is verified by analytical calculations, which also agree with preceding analyses for the limit of no curvature.