New technology enables record-setting performance with iron-based superconducting wires

A technology invented at the Department of Energy's Oak Ridge National Laboratory for manufacturing copper-oxide based high-temperature superconducting materials has been used to make an iron-based superconducting wire capable of carrying very high electrical currents under exceptionally high magnetic fields.

Researchers at Brookhaven National Laboratory took a RABiTS, or rolling-assisted biaxially textured substrate, comprised of a nickel-tungsten metal alloy with hetereoepitaxial buffer layers of Y2O3, YSZ, CeO2 and epitaxially deposited an iron-based high-temperature superconducting layer.

The work was published on-line 8 January in the journal Nature Communications.

The single-crystal-like RABiTS were developed in the 1990s by an ORNL team led by Corporate Fellow and Battelle Distinguished Inventor Amit Goyal. Iron-based high-temperature superconductors are a relatively recent discovery; many of the previous high-temperature superconductors were copper-based.

The iron-based superconductors can be synthesised at lower temperatures than the copper-oxide materials, and hence are seen as easier to work with. Brookhaven's experiment used RABiTS with a cerium oxide top layer.

The iron-based superconducting films deposited on the cerium oxide coated RABiTS exhibited significantly higher critical currents than could be previously obtained.