Advances in nanomachines

Citation

Rudall, B.H. (1998), "Advances in nanomachines", Kybernetes, Vol. 27 No. 8. https://doi.org/10.1108/k.1998.06727haa.001

Advances in nanomachines

Advances in nanomachines

Micron-sized machines

Many applications have already been published where minuscule machines have become essential to the required operations. Consequently, a great deal of effort has been put into research into such micromachines throughout the world. One of the leading teams developing such micro-electromechanical systems, micron-size machines, is based at the US's Sandia National Laboratories at Albuquerque. There the Intelligent Micromachine Department is managed by Jim Smith. This department, together with a research group at the University of California at Berkeley, USA, is extremely active and has already built a prototype that functions as a clock. This minuscule machine performs the same function as quartz crystals, which is the traditional technology used in timing devices in all electronic digital uses. Micromachines are, however, made from polysilicon, which is the same material used in manufacturing integrated circuits, the building blocks of digital electronics. This means that micromachines and integrated circuits can be constructed on one chip. Researchers suggest that if viewed through a powerful microscope the timing device prototype looks exactly like a double-ended tuning fork. It consists of two very fine strings or tines ­ ten would fit on a pinhead which are anchored in parallel to actuator frames the size of red blood cells.

Development of a molecular propeller

A report in the journal Science (July 1998) gives details of the work of scientists who have developed a molecular propeller that suffers no wear. Researchers at IBM's Zurich Research Laboratory in Switzerland and their co-researchers in France and Denmark have described this great advance in the development of nanomachines. Dr James Gimzewski of the Zurich Laboratory has described the propeller as being only 1.5 nanometre (just over a millionth of a millimetre) across. He believes that it could pave the way towards the development of machines, memories and calculators of molecules. He is quoted as saying that:

We do not envisage a molecular cuckoo clock but in ten years it could prove useful in computation or memory storage.

What the team have synthesised is a propeller-shaped compound which was used to form a single layer on a copper surface. Within this layer, some molecules acted like propellers, with others as bearings. When heat was applied, they began to rotate. This rotation can be seen through a scanning tunelling microscope, that is one that is able to scan a surface with a tip so sharp that it may end with a single atom. The researchers say that each of the propellers rotates so fast, at around 100 million times a second, that it appears as a blur. First assessments suggest that the rotor seems to be "wear-less". This the team believes, will be a great advantage when they have the task of creating gears and motors. It is believed that the motor will also help the scientific world to test ideas concerning the Second Law of Thermodynamics. This, as readers will know, rules out perpetual motion machines. We are told that no matter how carefully we design such a machine, a little of its useful energy will be converted into randomness, such as the jiggling of atoms.

Dr Gimzewski is said to believe that there is an argument over whether the Second Law holds true in all circumstances at the level of atoms and molecules. He says that:

With a single molecule we could hope to investigate this fundamental issue. The effort is part of a wider drive to use pollen-grained parts in everyday devices such as watches, televisions and computers. These measure at least 1,000 times larger than the propeller, but wear out.

The report in Science also included STM images which show the molecules immobilized and also spinning (at 100 million revolutions per second). The structure of the six-lobed "propeller" molecule was also displayed.

This is, of course, the beginnings of research work that has tremendous potential but we have been cautioned that the fruits of these endeavours will not be immediately available in marketable forms.