Carbon nanotubes have novel physical properties and they are promising materials for future technological applications. One of the most promising future applications is employing carbon nanotubes in electron field emission devices. Recent experiments showed that nanotubes have excellent field emission properties with high current density at low electric fields. Here, we present theoretical investigations that include geometrical effects and electronic structure of nanotubes. The electric field is dramatically enhanced near the cap of a nanotube with large variation of local field distribution. It is found that the deviation of Fowler-Nordheim behavior is due to the variation of local field in the electron-tunneling region. The maximum current per nanotube is at the order of 10 microA. Atomic scale aspects of field emission and simulated emission patterns will also be presented.
Journal: TechConnect Briefs
Volume: 3, Technical Proceedings of the 2003 Nanotechnology Conference and Trade Show, Volume 3
Published: February 23, 2003
Pages: 297 - 300
Industry sectors: Advanced Materials & Manufacturing | Sensors, MEMS, Electronics