Physicists Get the Dope on Disorder in High-Temperature Superconductors

摘要

Within high-temperature superconductors—layer-cake materials that carry current without resistance at temperatures as high as 130 kelvin—chaos reigns. To the vexation of physicists, key properties of the material vary randomly from place to place inside all but the most pristine samples. Some argue that the atomic-scale variations are a necessary ingredient of the superconductivity; others think they have nothing to do with it. Now, measurements reported on page 1048 reveal the source of much of the disorder: It's caused by oxygen "dopant" atoms strewn throughout the layered crystals—the same atoms that supply electric charges for the superconducting currents.