The world’s smallest fm transmitter made from 4 micrometre long graphene strip

Researchers have managed to use graphene for a useful application. By using the material’s unique properties, a few Americans managed to build the world’s smallest FM transmitter.

The small transmitter became developed by collaborators at Columbia University, who combined the mechanical and electrical properties of graphene into a nanomechanical electrical system. The nems transmitter, a scaled-down version of mems technique, uses the stretch in graphene to vary the frequency of a voltage-controlled oscillator. The frequency of the FM transmitter that the researchers built in this way is approximately 100MHz. With that they succeeded in modulating the song Gangnam Style using FM to send music to a conventional receiver.

The small piece of graphene was placed in a feedback circuit, which caused it to oscillate spontaneously. By varying the voltage of an electrode under the 2 to 4 micrometre long strip of graphene, the strip bends towards the electrode to a greater or lesser extent. The strain thus caused in the graphene modulates the resonance frequency.

For the time being, the graphene oscillators have a fairly low signal-to-noise ratio, which still needs to improve before a practical application can be found. The researchers think they can use their graphene oscillators in the future as components in Wi-Fi receivers and transmitters. The simple adjustment of the oscillation frequency of the graphene oscillators would allow for smaller circuits. In addition, the graphene could potentially be integrated with silicon circuits.