Self-detecting mechanical resonators made from suspended carbon nanotubes

We study the flexural and torsional mechanical properties of suspended carbon nanotubes. We have used a suspended carbon nanotube as a frequency mixer to detect its own mechanical motion. A single gate-dependent resonance is observed, which we attribute to the fundamental bending mode vibration of the suspended carbon nanotubes. Using a continuum model fit to the measurements, we show that the nanotubes in our devices have no slack and that, by applying a gate voltage, the nanotube can be tuned from a regime without strain to a regime where it behaves as a vibrating string under tension. We are currently investigating the low-temperature properties of these devices. We are also investigating the torsional mechanical properties of nanotubes.