Researchers from the National Institute of Standards and Technology (NIST) has discovered a new type of iron-based superconductor that shares the same magnetic properties with the older copper-oxide superconductors. The amazing fact is that the new superconductors have all those magnetic properties at higher temperatures.
“While we still do not understand how magnetism and superconductivity are related in copper-oxide superconductors,” explains NIST Fellow Jeffrey Lynn at the NIST Center for Neutron Research (NCNR), “our measurements show that the new iron-based materials share what seems to be a critical interplay between magnetism and superconductivity.”
Superconducting materials have the property of not tolerating magnetic fields at low temperatures. For example, the copper-oxide superconductors, discovered in 1986 only interfere with magnetic fields at very low temperatures, below 140 Kelvin (-133 Celsius).
Japanese researchers discovered earlier this year that a new class of iron-based superconducting materials also had much higher transition temperatures than the conventional low-temperature superconductors. The discovery sent physicists and materials scientists into a renewed frenzy of activity reminiscent of the excitement brought on by the discovery of the first high-temperature superconductors over 20 years ago.
Earlier work on the copper-oxide superconductors revealed that they have magnetically active copper-oxygen layers in their constitution, separated by layers of non-magnetic materials. By “doping,” or adding different elements to the non-magnetic layers of this normally insulating material, researchers can manipulate the magnetism to achieve electrical conduction and then superconductivity.
Superconductivity has been available by now only to specialized labs and scientists. If it can be achieved at higher temperatures, it can help the green nature of electric motors, electricity transportation, and improve the functioning of high speed data circuits by removing the greatest loss source: heat. That means more efficiency, less power used to get the same effect, and less pollution.