Tuning In With A Nanotube

Radio has gone nano. Electrical engineers at the University of California, Irvine, have built a radio receiver that uses a carbon nanotube as a key component (Nano Lett., DOI: 10.1021/nl0714839). Peter J. Burke and Chris Rutherglen employed the nanotube as a demodulator—the device that translates radio waves into sound. The UC Irvine team grew nanotubes on high-resistivity silicon and then grafted palladium electrodes onto the wafer by optical lithography. For the demodulator, the researchers selected devices in which a lone nanotube bridged the gap between electrodes. They then incorporated the nanotube demodulator into an AM radio receiver. Using an iPod and an AM signal generator as their broadcasting system, Burke and Rutherglen showed they could wirelessly transmit music to the nanotube receiver system while maintaining high audio quality. The demodulator isn't limited to AM radio, Burke tells C&EN; the nanotube device could work with other broadcasting systems, such as FM radio or cellular phone signals.