Influence of defects on carrier injection in carbon nanotubes with defects

Abstract

Based on density functional theory, we study the electronic properties of carbon nanotubes (CNTs) with divacancy, C2 adatom, and Stone–Wales defects under an electric field. These defects intrinsically induce an internal electric field in CNTs because of the modulation of the electrostatic potential arising from the defects. According to the internal electric field induced by the defects, the threshold gate voltage required to accumulate electrons and holes strongly depends on the defect species and their relative positions in the CNTs with respect to the electrode. The results suggest that the defects result in large gate voltage variations for both electron and hole injection, causing the degradation of CNT-based electronic devices.