Superconductivity Seen Above the Boiling Point of Nitrogen

Since the observation by Karl Alex Müller and Johannes Georg Bednorz (IBM Zurich) in January 1986 that an oxide of barium, lanthanum and copper might be superconducting at temperatures up to 35 K, several groups around the world have reported seeing superconductivity above 90 K in a number of ternary oxides containing rare earth elements. Many laboratories are already exploring applications for these materials. Why they are superconducting at such high temperatures is one of many questions that theorists are trying to answer.