Gigahertz nanomechanical oscillators based on carbon nanotubes

We report molecular dynamics studies of carbon nanotubes as mechanical gigahertz oscillators. Our results show that different oscillatory regimes exist but that sustained oscillations are possible only when the radii difference values of the inner and outer tubes are similar to3.4 Angstrom. Frequencies as large as 87 GHz were obtained. Calculated force and frequency values are in good agreement with estimated data from recent experimental investigations.