Nanomagnet switches that assemble themselves

The finer these magnetic structures are, the greater the density of data and thus their storage capacity. In 2011 KIT scientists led by Professor Mario Ruben at the Institute of Nanotechnology (INT) working with experts from Grenoble and Strasbourg constructed a nanomagnet switch that could generate significantly finer structures than had previously been possible. A particularly clever idea was to employ the same principle of self- organisation as commonly found in natural processes. The researchers applied adhesion principles to the magnet molecules in such a way that the latter docked onto a nanotube in the desired position. The resulting magnetic switch consists not of silicon, metals, oxides or semiconductors, but of carbon nanotubes and organic molecules. The molecules used in this process contain a single atom of the metal terbium, which introduces magnetism into the system. The terbium atom is embedded in the organic material and reacts to even the tiniest external magnetic field. When electrical current flows through the carbon nanotubes, it is altered to such a degree that this change can be read externally as a signal. This effect could make it possible to generate greater storage densities as well as new types of structural elements for quantum computers. However, at present the nanomagnet switch only functions at temperatures close to absolute zero, and the scientists are now working on ways to apply the same principle at higher temperatures.

Forschungszentrum Jülich/red.