Graphene used to create 'smallest' FM radio transmitter

In other words, they've built what they believe to be the world's smallest FM radio transmitter. "This work is significant in that it demonstrates an application of graphene that cannot be achieved using conventional materials," said lead researcher Professor James Hone. "And it's an important first step in advancing wireless signal processing and designing ultra thin, efficient mobile phones." To create the transmitter, the researchers utilised graphene's exceptional mechanical properties to tune the output frequency of their custom oscillator, creating a nano-mechanical version of a voltage controlled oscillator. They then built a graphene NEMS with a frequency of about 100MHz, which lies right in the middle of the FM radio band (87.7 to 108MHz). Low frequency musical signals (both pure tones and songs from an iPhone) were used to modulate the 100MHz carrier signal from the graphene. These were then retrieved again using an ordinary FM radio receiver. "This device is by far the smallest system that can create such FM signals," noted Hone. "There is a long way to go toward actual applications in this area, but this work is an important first step. "We are excited to have demonstrated successfully how this wonder material can be used to achieve a practical technological advancement - something particularly rewarding to us as engineers."