Structural deformations and current oscillations in armchair-carbon nanotube cross devices: a theoretical study

Abstract

A carbon nanotube (CNT) cross is a structure consisting of two CNTs with one draped over the other at an angle. Because of the localized mechanical deformation induced at the intersection point, the electronic properties of the nanotubes in a cross could vary significantly compared with those of intact nanotubes, potentially leading to the formation of nanoscale quantum dots.Using classical molecular dynamics, we determined the relaxed nanotube structures and the induced mechanical deformations in a CNT cross. We found that the final relaxed shape of the cross structure is relatively insensitive to the starting shape. We then calculated the electronic transport properties of this device using a first-principles, non-equilibrium Green's function approach. We obtained current oscillations that can be attributed to the formation of a nanoscale quantum dot in the top nanotube at the intersection region.