Graphene's good vibrations for supersensitive detectors

Graphene and its curlier cousin, the carbon nanotube, could revolutionise yet another field, as researchers find that when built into teeny tiny resonators, they have been shown to exhibit non-linear damping.

Oh-ho, you say, this could lead to supersensitive devices to detect force or mass. Well, yes indeed it could, according to the researchers behind the discovery at the Catalan Institute of Nanotechnology.

Or you might say "eh?" So lets go into a bit more detail.

Resonators, such as those made from quartz, are used in circuits to generate signals with a specific and precise frequency. They are made by suspending the resonating material between two anchors, and tuning it to the desired pitch. The devices are used in watches and computers to keep time, and in radio transmitters, to stabilise the output signal.

Now, led by Professor Adrian Bachtold, this is exactly what the CNT team has done with graphene, but instead of behaving in a predictable and linear way, the vibrating strings of graphene and carbon nanotubes come back to rest quite differently. This characteristic could be used to amplify tiny signals, leading to huge improvements in device sensitivity.

From the press release: "The finding has profound consequences. Damping is central to the physics of nanoelectromechanical resonators, lying at the core of quantum and sensing experiments. Therefore many predictions that have been made for nanoscale electro-mechanical devices now need to be revisited when considering nanotube and graphene resonators."

The work will be published in the journal Nature – Nanotechnology.