Dreams Into Reality

Superconductivity may be turning scientists into visionaries, but their dreams of flying trains and of cheap power are hobbled by a problem. The new ceramic superconductors carry electricity with perfect efficiency at far higher temperatures than conventional superconductors (above -320 degrees F, vs. -418 degrees F or below), making them easier to refrigerate and cheaper to use. But to be useful, they must carry at least 100,000 amps of current per square cm of cross section and 1 million amps or more in some applications. So far, the new superconductors have carried only about 1,000 amps.

No more. IBM scientists announced last week that a crystal about the size of a quarter but only one-hundredth the thickness of a human hair has handled more than 100,000 amps. Other obstacles remain, including the difficulty of molding the new material. But, says IBM's Praveen Chaudhari, "if you told me two weeks ago that we would have high-temperature superconductors that carry high currents, I would have said you were dreaming. Now if someone told me we will have useful devices made of this material next month, I wouldn't call him a dreamer. That's how fast this field is moving."