THE BAND-GAP AND TRUE BAND-GAP IN NOMINALLY METALLIC CARBON NANOTUBES: THE TIGHT-BINDING STUDY ON CORRUGATION EFFECT

Abstract

In this paper, the band-gap and true band-gap are analyzed for the corrugated structures of various types of single wall carbon nanotubes (SWCNTs) within the tight binding approximation. We show that corrugation, combined with curvature effect, yields naturally the true small band-gap in all SWCNTs with small radius. The more stable corrugated structures of SWCNTs are backed by the abinitio total energy calculations for nominally metallic armchair SWCNTs.