  Recently Zheng and Jiang [PRL 88, 045503 (2002)], based on static models,
have proposed that multiwalled carbon nanotubes could be the basis for a new
generation of nanooscilators in the several gigahertz range. In this work we
present the first molecular dynamics simulation for these systems. Different
nanotube types were considered in order to verify the reliability of such
devices as gigahertz oscillators. Our results show that these nanooscillators
are dynamically stables when the radii difference values between inner and
outer tubes are of ~ 3.4 A. Frequencies as large as 38 GHz were observed, and
the calculated force values are in good agreement with recent experimental
investigations. Moreover, our results contradict some predictions made by Zheng
and Jiang.
