Effects of curvature on the electronic structures of single-walled carbon nanotubes

Abstract

Based on the energy dispersion relation involving curvature effects for the single-walled carbon nanotube (SWCNT), the electronic velocity and the effective mass of the lowest conduction band for the SWCNT are computed and they are compared with the results without consideration of the curvature effects. The analysis shows that the influences of the curvature effect on the electronic velocity and effective mass depend on type of SWCNT, that is, the metallic zigzag-SWCNT is most sensitive to curvature effect, armchair-SWCNT is second most sensive to curvature effect, and the semiconducting zigzag-SWCNT is poorly sensitive to curvature effect. These findings suggest that curvature effects have the largest effect on the electronic structure and the low-bias transport behaviors of the metallic zigzag-SWCNT,a moderate effect on those of the armchair-SWCNT, and the smallest effect on those of the semiconducting zigzag-SWCNT, which are in good agreement with experimental measurements and the calculated results from the density-functional theory.