Single Nanotube Becomes World's Smallest Radio

Invisible Pink Unicorn writes "Researchers at the National Science Foundation have utilized a single carbon nanotube to perform all the functions of a standard radio, acting as an antenna, tunable filter, amplifier, and demodulator. They were then able to tune in a radio signal generated in the room and play it back through an attached speaker. The device is functional across a bandwidth widely used for commercial radio. From the NSF: 'The source content for the first laboratory test of the radio was "Layla," by Derek and the Dominos, followed soon after by "Good Vibrations" by the Beach Boys.'"

Comments

Journal abstract and Project page

[InvisblePinkUnicorn]

Their project page has videos, simulations, and audio playback samples: NSF Nanotube Radio

Here is their journal abstract:

"We have constructed a fully functional, fully integrated radio receiver from a single carbon nanotube. The nanotube serves simultaneously as all essential components of a radio: antenna, tunable band-pass filter, amplifier, and demodulator. A direct current voltage source, as supplied by a battery, powers the radio. Using carrier waves in the commercially relevant 40-400 MHz range and both frequency and amplitude modulation techniques, we demonstrate successful music and voice reception."

Going full circle

[sm62704]

In the 19th century they had pocket watches. Then watches got small enough to strap on your wrist. Then we got cell phones, threw away our wristwatches and put the phone in a pocket.

In the 19 century we had vacuum tubes. In the mid 20th century these were replaced by semiconductors, which were smaller and less bulky. Now we're back to tubes again, and the TFA sounds like these are kind of nano vacuum tubes, only without the vacuum.

The nanotube radio is likely like these geek toys nerds have been building since the early 1900s. All you need to build one is a diode, some wire, a piece of wood, and headphones to listen to it with. They used to call these things "catwhisker radios", the "cat whisker" being the diode.

-mcgrew