Oscillators based conventional resonators such as quartz crystals require considerable off-chip space. That's a problem that researchers at Columbia University were looking to address by building µm-scale atomically thin graphene nanomechanical resonators. The resonators are a subset of what the researchers call nanoelectromechanical systems (NEMS)—scaled-down versions of MEMS.
The researchers report that they can electrostatically tune the resonators' frequency by as much as 14%—enabling them to demonstrate the use a graphene oscillator to transmit an audio signal using a frequency-modulated 100-MHz carrier.
The research was led by led by Mechanical Engineering Professor James Hone and Electrical Engineering Professor Kenneth Shepard. Writer Holly Evarts at Columbia quotes Hone as saying, “This work is significant in that it demonstrates an application of graphene that cannot be achieved using conventional materials. And it’s an important first step in advancing wireless signal processing and designing ultrathin, efficient cell phones. Our devices are much smaller than any other sources of radio signals, and can be put on the same chip that’s used for data processing.”
The research is described in a paper published November 17 in Nature Nanotechnology. If you are not a subscriber, you can purchase a copy here for $32, or you can read Evarts's summary here.