Volume 78, Number 4, May 2007
Article Number 47002
Number of page(s) 6
Section Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
Published online 10 May 2007
EPL, 78 (2007) 47002
DOI: 10.1209/0295-5075/78/47002

Geometry-induced smoothing of van Hove singularities in capped carbon nanotubes

D. V. Kolesnikov and V. A. Osipov

Joint Institute for Nuclear Research, Bogoliubov Laboratory of Theoretical Physics - 141980 Dubna Moscow region, Russia

received 22 December 2006; accepted in final form 11 April 2007; published May 2007
published online 10 May 2007

The electronic states of capped semi-infinite nanotubes are studied within the phenomenological gauge field-theory model. A single manifold for the description of both the nanotube and the cap region (considered as nearly a half of either Ih or I fullerene) is suggested. The wave functions and the density of states (DoS) are numerically calculated for both metallic and semiconducting nanotubes. The smoothing of van Hove singularities is found and proven analytically. The comparison with the experimental observations is discussed.

73.22.-f - Electronic structure of nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals.
71.20.Tx - Fullerenes and related materials; intercalation compounds.
73.22.Dj - Single particle states.

© Europhysics Letters Association 2007