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New Class of High-T Superconductors: since the discovery of high-temperature superconductors in 1986, all had been a ceramic made up of lanthanum-barium-copper oxides. Earlier this year, there was a flurry of papers from a number of research groups that announced they had found a new class of high-temperature superconductors, ceramics made of lanthanum, iron, arsenic, oxygen, and fluorine. While their critical temperature is, by high-temperature superconducting standards, a not-so-hot 55 K, they have opened a new pathway into the mystery of superconductor research. Follow up work hasn't been able to determine whether these materials behave the same as their more familiar cuprate cousins.

On Feb. 6, 2009, Southwire Company and its partners mark the two-and-a-half year anniversary of an urban power distribution project using high-temperature superconductor— known as HTS Triax® Superconducting Cable systems.The installation in Groveport, OH used about 200 meters (600 feet) of Southwire’s HTS Triax Superconducting Cable to distribute electric power to 8,600 homes and businesses through American Electric Power’s Bixby substation. In addition to American Electric Power (AEP), project partners included American Superconductor, the U.S. Department of Energy’s Oak Ridge National Laboratory, and Praxair.

The New Zealand-made high temperature superconductor carries up to 10 times the current of copper wire of the same size, without energy loss. In a world-first, the New Zealand scientists have produced commercially viable superconductor wire and cable – reliable, robust and economical. It consists of strips of a new material thinner than paint and sheathed in metal.

American Superconductor said this week that it will work with the Department of Energy’s National Renewable Energy Laboratory and its National Wind Technology Center to look at the economics of building a 10-MW turbine. The Devens, Mass.-based company said it can get a bigger power punch but still keep the size and weight under control by using its high temperature superconductor wire, which it claims is lighter and more efficient than the copper wire traditionally used in wind turbines.

The highest transition temperature found up to now – the temperature below which a material becomes superconducting – was for a cuprate, a copper compound, and lies at 166 K (-107°C). The problem is that cuprates have a similar consistency to graphite, which we know from pencil leads. Cuprates are difficult to work mechanically; for example, attempts to produce long wires from them have hitherto been unsuccessful. Cuprates are also difficult to manufacture and are often toxic.

The new iron-arsenic materials are the first relatively high-temperature materials that remain superconducting above a temperature of 50 K that don't contain copper; the copper materials are brittle.