Title: Migration of a Carbon Adatom on a Charged Single-Walled Carbon Nanotube,
Abstract: We find that negative charges on an armchair single-walled carbon nanotube
(SWCNT) can significantly enhance the migration of a carbon adatom on the
external surfaces of SWCNTs, along the direction of the tube axis. Nanotube
charging results in stronger binding of adatoms to SWCNTs and consequent longer
lifetimes of adatoms before desorption, which in turn increases their migration
distance several orders of magnitude. These results support the hypothesis of
diffusion enhanced SWCNT growth in the volume of arc plasma. This process could
enhance effective carbon flux to the metal catalyst.