The research suggests that the material may have future applications including improved magnetic resonance imaging machines, and a new generation of superconducting electric motors, generators and power transmission lines.
Research on this substance is very much in its early stages, but the scientists are talking excitedly of "promise" and "potential".
The team includes Frank Hunte, a postdoctoral associate at the Applied Superconductivity Center, and David Larbalestier, Alex Gurevich and Jan Jaroszynski from the Oak Ridge National Laboratory in Tennessee.
"What we would like is a greater selection of superconductors, operating at higher temperatures, being cheaper and more capable of being made into round wires," said Larbalestier.
"Iron and arsenic, both inherently cheap materials, are key constituents of this totally new class of superconductors. We are just fascinated. It is superconductivity in places you never thought of."