Discovery May Lead To Precision Engineering of Superconducting Electronic Devices

Using precision engineering techniques for making superconducting thin films layer-by-layer, physicists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory have identified a single layer responsible for one such material's ability to become superconducting, i.e., carry electrical current with no energy loss. The technique, described in the October 30, 2009, issue of Science, could be used to engineer ultrathin films with "tunable" superconductivity for higher-efficiency electronic devices.

Brookhaven physicist and the group leader Ivan Bozovic said that:

"We wanted to answer a fundamental question about such films, how film can be made thin and still retain high-temperature superconductivity?"

The thinner the material (and the higher its transition temperature to a superconductor), the greater it’s potential for applications where the superconductivity can be controlled by an external electric field used by precision engineering company.

Bozovic explained that:

"This type of control is difficult to achieve with thicker films, because an electric field does not penetrate into metals more than a nanometer or so,"

The material studied by Bozovic's team was unusual in that it consists of layers of two materials, one metallic and one insulating, that are not superconductors on their own, but rather exhibit superconductivity at the interface between them.

The layer identified as essential to the superconductivity by the zinc-substitution experiment represents the second copper-oxide layer away from the interface. During application of precision engineering services, the scientists found that the presence of zinc had no effect on the transition temperature at which superconductivity sets in, about 32 kelvin (-241 Celsius), except when placed in that particular layer.

Bozovic explained that, in the material he studied, the electrons required for superconductivity actually come from the metallic material below the interface. Thus precision engineering of superconducting electronic devices could be made more useful for the common man, as well as for professional engineering purposes.