Emission spectrum of a driven nanotube oscillator as a function of frequency (left axis) and drive power (bottom axis).

Our paper A coherent nanomechanical oscillator driven by single-electron tunnelling is online in Nature Physics today.

When electrical leads are attached to a suspended carbon nanotube, the nanotube’s motion can be detected from changes in the electrical current that passes through it. At the same time, the nanotube experiences a fluctuating electrostatic force depending on the number of electrons present. Our paper shows that the feedback between these two effects can generate a coherent mechanical oscillation, driven purely by the d.c. current through the device.