Numerical Modeling of Single-wall Carbon Nanotubes Electromechanical Coupling Effects Using Nanoscale Models

Macroscopic electrical properties of carbon nanotubes are determined by their atomic and electronic structure. The analysis involves three interconnected phases. The Tight-Binding Approximation theory is first employed to predict the electronic band structure of the nanotube. Effects of nanotube wall curvature and the presence of an external electric field are included in the formulation. Subsequently the nanotube electrical resistance is calculated using the Wentzel-Kramers-Brillouin and Miller-Good approximations. The coupling effects between mechanical deformation and electrical resistance variations of a carbon nanotube are finally modeled. Numerical results illustrate the sensitivity of the band gap and the electrical resistance to nanotube configuration, and induced axial and torsional strain. The influence of wall curvature and an externally applied electric field on the tube resistance are also illustrated. Finally the differences in the prediction of electric resistance obtained by the Wentzel-Kramers-Brillouin and Miller-Good approximations are also shown.