Collapsed Semiconducting Nanotubes Having Degenerate Band at Fermi Level Due to Broken Axial Symmetry

Abstract

Full collapsed semiconducting nanotubes became metallic, having singly degenerate band at Fermi level due to broken symmetry. It was found that wave function used was mismatched, which leaded to higher contact resistance in respect of ideal contact. A new method was used for degeneracy lifting due to interaction among π-orbitals on sidewalls of collapsed nanotube produced larger magnitudes of bands and were splitted in fully collapsed carbon nanotubes. A continuum model was considered for  explanation of carbon atoms in carbon nanotubes with metal. For this purpose a semiatomistic model was used for description of positions of carbon atoms in the presence of metal and substrate. Carbon nanotube interatomic interactions were explained by valence force model considering stiffness opposite to misalignment of neighboring π-orbitals for reduction of bending stiffness. Substrate was planar and rigid but metal was isotropic. Deformations on electronic structures were created due to effect of metal induced nanotube. Band gap reduction was found in deformed carbon nanotubes and increased metal induced doping of nanotube, which reduced the resistance by means of conduction channels, mismatched function and scattering at contact.