We have performed first-principles calculations on the field emission of carbon nanotubes. The three-dimensional character of the current source, as well as the effect of the external electric field, are explicitly considered. The calculated electron-leakage by solving the time-dependent Schrödinger equation is quite linear in short time scale, giving the tunneling rate from the emitter to the vacuum. The total current fits the Fowler-Nordheim formula reasonably well. The magnitude of the current associated with each electronic state is found to exponentially depend on the energy level. We have also performed first-principles pseudopotential calculations for the electronic structure of fullerenes such asC82 encapsulated in single-walled carbon nanotubes. We find a charge transfer occurs between the carbon nanotube (CNT) and C82, and states are produced by the hybridizaion of C82 and the CNT.
Journal: TechConnect Briefs
Volume: 2, Technical Proceedings of the 2002 International Conference on Computational Nanoscience and Nanotechnology
Published: April 22, 2002
Pages: 291 - 294
Industry sectors: Advanced Materials & Manufacturing | Sensors, MEMS, Electronics