WC Archive

Oh, carbon nanotube, is there nothing you cannot do? Probably, but it's time to add another item to the list of carbon nanotube uses. Researchers at UC Irvine have figured out how to construct a high speed nanotransistor using a single-walled carbon nanotube. This is a good step towards nanoscale computers. Moreover, this early-stage work suggests that carbon nanotube-based computers would be able to operate significantly faster than current-generation silicon-based chips, and perhaps faster than the maximum possible speed for silicon technology.

Although Burke's group demonstrated that nanotube transistors could work in the GHz range, he believes that much faster speeds are possible. "I estimate that the theoretical speed limit for these nanotube transistors should be terahertz [1 THz=1,000 GHz], which is about 1,000 times faster than modern computer speeds." His team is currently doing related research on the theoretical prediction of the cutoff frequency, or so-called speed limit, for these transistors.

Every transistor has a cutoff frequency, which is the maximum speed at which it can operate. For silicon, the cutoff is about 100 GHz, but current circuits typically operate at much slower speeds, according to Burke.

The usual caveats -- it's early work, it will take a couple of years to come to fruition, they may run into unexpected problems, etc. -- apply. But this is another good indicator that the acceleration of information technology is nowhere close to reaching its limits.