Molecule Walks Like a Human

September 28, 2005 | Source: KurzweilAI

The “nano-walker,” a molecule that can move in a straight line on a flat surface has been designed by UC Riverside researchers, offering a new approach for storing large amounts of information on a tiny chip.

A DTA molecule moves in a straight line on a flat surface, such as a copper sheet shown here, by mimicking a human walking

A DTA molecule moves in a straight line on a flat surface, such as a copper sheet shown here, by mimicking a human walking

The molecule — 9,10-dithioanthracene or “DTA” — has two linkers that act as feet. Obtaining its energy from heat supplied to it, the molecule moves such that only one of the linkers is lifted from the surface; the remaining linker guides the motion of the molecule and keeps it on course. Alternating the motions of its two “feet,” DTA is able to walk in a straight line without the assistance of nano-rails or nano-grooves for guidance.

Ordinarily, molecules move in every unpredictable direction when supplied with thermal energy.

According to research team leader Ludwig Bartels, assistant professor of chemistry and a member of UCR’s Center for Nanoscale Science and Engineering, “This offers an easy realization of a concept for molecular computing proposed by IBM in the 1990s, in which every number is encoded by the position of molecules along a line similar to an abacus, but about 10 million times smaller. IBM abandoned this concept, partly because there was no way to manufacture the bars of the abacus at molecule-sized spacing.

“DTA does not need any bars to move in a straight line and, hence, would allow a much simpler way of creating such molecular memory, which would be more than 1000 times more compact than current devices.”

The UCR research team is now trying to build a molecular ratchet, which would convert random thermal oscillation into directed motion.

Source: UC Riverside news release and Physical Review Letters (forthcoming)