Indian scientists in the U.S. have created history by making the world’s tiniest transistor entirely made from carbon nanotubes. Nanotubes are rolled up sheets of carbon atoms and are thousand times thinner than human hair. The innvoation heralds a new era of ultra miniature electronics where standard silicon transistors are replaced with much smaller versions fashioned from carbon nanotubes.

The new transistor is a Y-shaped nanotube with two branches that meet a central stem at a junction. The current flowing from one branch to another can be switched on and off by applying voltage to the third. Such binary logic called “gating” is the basis of nearly all transistors.

“The small size and dramatic switching behavior of these Y-shaped nanotubes make them candidates for a new class of all-carbon transistor,” says Prabhakar Bandaru, a materials scientist at the University of California, San Diego who led the team that included his colleague Sungho Jin, graduate student Chiara Daraio and physicist Apparao M.Rao at Clemson University in South Carolina.

Conventional transistors like those in Pentium chips are built from layers of semi conducting silicon but the chip size has already shrunk to a size that cannot get any smaller. The quest for ever-smaller chips has driven scientists worldwide to explore nanotubes. They have already made logic circuits using nanotubes but these required metal ‘gates’ to control the flow of current.

One must remember that even for the Pentium chips used in our computers (which now have over 300 million transistors), the progenitor was a simple integrated circuit with two transistors made in 1958.

Indian scientists may have missed the semiconductor revolution of the 1960’s that heralded the era of computers based on silicon. But when the era of nanoelectronics dawns on the world they sure are to be in the driver’s seat.