"Key” genetic search of novel electrical crystals

After creating a master ''ingredient list'' describing the properties of more than 2,000 compounds, Duke University engineers have now developed the a key to turning these ingredients into the next generation of electrical components.

The electrical compounds are known as topological insulators (TI), man-made crystals that are able to conduct electrical current on their surfaces, while acting as insulators throughout the interior of the crystal. Discovering TIs has become of great interest to scientists, but because of the lack of a rational blueprint for creating them, researchers have had to rely on trial-and-error approaches, which to date have had limited success.

Because of their unique properties, TIs can be created so that they can not only conduct electricity more efficiently, but can be fashioned to be much smaller that conventional wires or devices, making them ideal candidates to become quantum electronics devices, the Duke researchers said.

The ''key'' developed by the Duke investigators is a mathematical formulation that unlocks the data stored in the database and provides specific recipes for searching TIs with the desired properties.

''While extremely helpful and important, a database is intrinsically a sterile repository of information, without a soul and without life. We need to find the materials 'genes','' said Stefano Curtarolo, professor of mechanical engineering and materials sciences and physics at Duke's Pratt School of Engineering and director of the Duke's Center for Materials Genomics. ''We have developed what we call the 'topological descriptor,' that when applied to the database can provide the directions for producing crystals with desired properties.''

Finally the team discovered a new class of systems that could have been hardly anticipated without such a genetic approach.