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No Resistance; August 2000; Scientific American Magazine; by Bruce Schechter; 2 Page(s) For a few months in 1987, it seemed the world was about to change. Trains would fly on magnetic cushions, computers would be faster, electric power cheaper, new medical scanners would sprout in doctors' offices and more. The reason for this overheated optimism was the discovery by IBM scientists in Zurich, namely, J. Georg Bednorz and K. Alex Muller, of a new kind of superconductor, an almost miraculous material that conducts electricity without any loss of energy. Superconductors had been around since 1911, but all known superconductors worked at near absolute zero, which made them impractical for all but the most specialized applications. The discovery led to a class of oxide superconductor working well above the temperature of liquid nitrogen. Boiling at 77 kelvins, liquid nitrogen is much less expensive to make and far easier to handle than liquid helium, which cools conventional superconductors. (Physicists still hope to find a material that superconducts at room temperature-possibly the next best thing to perpetual motion.) Gradually, researchers have found ways to craft high-temperature superconductors into useful magnetic components for research and for medical diagnostics and have even manufactured motors, current limiters and other devices for demonstration purposes. But now, more than a decade after their discovery, they are entering two markets closer to the consumer realm-power lines and wireless communications.
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