High-Temperature Superconductors  

Science reports that a second family of (relatively) high-temperature superconductors has been discovered.

Superconductors are interesting from an energy transmission point of view because of the very low losses involved. The gain compared to other transmission methods is partially offset by the energy required to refrigerate the lines, so high temperature superconductors are an interesting advance for those considering building large scale supergrids - such as the US plan for a superconducting cable network covering the entire nation by 2030.

Researchers in Japan and China have discovered a new family of high-temperature superconductors--materials that conduct electricity without any resistance at inexplicably high temperatures. Physicists around the world are hailing the discovery of the new iron-and-arsenic compounds as a major advance, as the only other high-temperature superconductors are the copper-and-oxygen compounds, or cuprates, that were discovered in 1986. Those older materials netted a Nobel and ignited a firestorm of research, but physicists still don't agree about how they work, leaving high-temperature superconductivity the biggest mystery in condensed matter physics. Some researchers hope the new materials will help solve it.