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High-temperature superconducting magnets may become important in the maglev, or magnetically levitated, trains under development in Japan and West Germany. And scientists at Japan's Mercantile Marine University in Kobe have already developed a working scale model of a ship with a propulsion system based on magnetism. Physicist Yoshiro Saji sends current through the seawater from an onboard electric generator via ship-bottom electrodes. A superconducting magnet, also on board, creates a strong magnetic field. As the electromagnetic field produced by the electric current pushes against the field of the magnet, the ship moves forward. Saji has already moved up his timetable and hopes to complete a 100-ton "magship" within four years. "Thanks to the new materials," he says, "magnets will be lighter and easier to handle. Once we can replace liquid helium with liquid nitrogen, the whole process of outfitting the ship will be simplified. It's a fantastic development."
On a smaller scale, superconductors have already been used to create superfast electronic switches called Josephson junctions (after Nobel Laureate Brian Josephson, the British physicist who discovered the principle on which they are based), which until now could operate only at liquid-helium temperatures. For both technical and economic reasons, IBM abandoned its Josephson junction project in 1983. But IBM Physicist Sadeg Faris quit the company, obtained licenses for the technology and formed Hypres, Inc., which has begun marketing its first Josephson junction product -- a high-speed oscilloscope. Says Faris: "The new materials are at a primitive stage, but we're anxious to exploit them to bring down costs and improve speed." Since switches are a limiting factor in computer speed, an economical Josephson junction could prove invaluable.
At Westinghouse, scientists are working on the idea of using superconductors for electric-power production. Today's nonsuperconducting generators produce electricity by spinning wire-wrapped rotors in a magnetic field; their output is typically some 300 megawatts a generator. If the field were generated even by conventional superconducting electromagnets, says Research Director John Hulm, the output could be doubled. The benefits would be even greater with high-temperature superconductors.
And then there are the daydreams: giant underground loops of superconducting cable that can store vast amounts of electricity for later use; cars that run on tiny, powerful electric motors, drawing current from superconducting storage devices. But even the daydreams are taken at least somewhat seriously. At Ford, for example, a study group has been assembled to rethink the feasibility of the electric car in light of the recent advances in superconductivity. Says IBM Physicist John Baglin: "The question is not 'How can we take this material and do something everyone has wanted to do?' but 'How can we do something that no one has yet imagined?' " Some tongue-in- cheek suggestions overheard at a superconductor meeting: superconducting ballroom floors and rinks that would enable dancers and skaters literally to float through their motions.