Researchers Create Tiny Nanotube Radio

Nanotube technology is finally showing its true power by creating the first nanotube radio out of carbon nanotube materials. This represents an important step for the introduction of carbon nanotube structures into the world of analog electronics and applications that derive directly from this branch. The claim is detailed by John Rogers, from the Materials Science and Engineering at the University of Illinois, which is a corresponding author to the paper describing the design of the new nanotube radio.

The nanotube growth techniques developed by Rogers, in collaboration with engineers from Northrop Grumman Electronics Systems, enable them to build nanoscale structures that have significant advantages in comparison with the traditional silicon semiconductor chips, but could also be used to complement for a series of semiconductor materials.

Rogers used growth technologies that enabled him to produce arrays of thousands of carbon nanotubes, linear or horizontally aligned, which can be made to function as a single entity similar to silicon semiconductors, in which electric charges move freely. Furthermore, the team has shown that the nanocarbon structures can be integrated into electrical logical circuits in order to be used in the future chip manufacturing technologies.

The team also attacks one of the most important features of nanostructures, the ability to carry high current loads. By creating horizontal arrays of densely-packed carbon nanotubes, nanotechnology is currently able to manufacture high performance transistors. Rogers says that one of the most sensitive areas for carbon nanotube in the field of electronics is that of analog radio frequency, but this step has already been surpassed with the invention of the first carbon nanotube radio.

The carbon nanotube radio, built by engineers from Northrop Grumman, used the principle of traditional radio receivers, in which all the functions of the semiconductor transistor were provided by nanotube transistors. Rogers explains: Northrop Grumman fabricated a series of nanoscale radios that function on the basis of the modulating receiver design, which involves the use of four additional stages, coupled between each other by capacitive couplers. One of the stages is used for the resonant antenna, two for the radio-amplifiers and one as an audio signal amplifier.

The audio signal was obtained directly from the output terminal of a nanotube transistor, and each of the manufactured nanotube radios contained seven different constructive types of nanotube transistors. However, Rogers warns that his work should not be mistaken with an attempt to create the world's smallest transistor radio; the team was only trying to prove that carbon nanotube transistors could be used efficiently in mass production electronic devices.