물리학자들이 초전도체를 발견하다.

준비된 유용한 금속합금이 예상치도 못하게 최근의 초전도체로 변하였다...라고 신문에 났더군요. 오늘날자 뉴욕타임즈에...기사두 올립니당..구럼... February 24, 2001 Physicists Thrill to Finding of Superconductor By KENNETH CHANG A readily available metallic compound has unexpectedly turned into the latest breakthrough superconductor. The compound, magnesium boride, known since the 1950's, is commonly used for some chemical reactions, but no one had ever tested whether it would become a superconductor at low temperatures, able to ferry electricity with virtually no resistance. At a scientific conference in Sendai, Japan, in early January, researchers led by Dr. Jun Akimitsu of Aoyama Gakuin University in Tokyo announced that magnesium boride was a superconductor and remained a superconductor at temperatures up to minus 389 degrees, or about 29 degrees higher than any other simple metallic compound. A report about their findings will be published in next week's issue of the journal Nature. In the month and a half since the conference in Japan, researchers around the world have rushed to investigate the compound. "We've seen a big increase in demand since the word got out about its superconducting properties," said John Shirley, catalog sales and marketing manager at the chemical supply company Alfa Aesar in Ward Hill, Mass., which sells 100-gram bottles of the chemical for $174 each. "You could have bought the stuff and measured it, and it would have been superconducting," said Dr. George W. Crabtree, a senior scientist at Argonne National Laboratory in Illinois. "It's just amazing. You don't even have to make it. This could have been found 50 years ago." While other, more complex superconducting materials work at higher temperatures, magnesium boride is relatively inexpensive, raising hopes that it might eventually find applications in magnetic resonance imaging machines, more efficient power transmission lines and a variety of electronic devices. The material is also very light and appears to be not as difficult to work with as the copper oxides in the so-called high-temperature superconductors. Dr. Paul C. Canfield, a professor of physics at Iowa State University at Ames and a researcher at Ames Laboratory, heard about Dr. Akimitsu's discovery a couple of days after the conference. "It's a fantastic discovery," Dr. Canfield said. "We've been able to do a lot of neat stuff with it in the past month." Dr. Canfield said he and his colleagues at Iowa State and Ames Laboratory had been working long hours seven days a week investigating magnesium boride. Several experiments suggest the compound works like traditional superconductors like niobium and not like high-temperature superconductors, which still are not fully understood. The Iowa researchers have already fashioned superconducting wires by exposing fibers of boron to magnesium vapors. At present, though, the wires are short, a couple of inches long, and brittle. "It's not something you can curl around your finger," Dr. Canfield said. Physical Review Letters has accepted for publication three papers from the Iowa researchers. A fourth paper has been submitted to Physical Review. Announcement of the high-temperature superconductors 15 years ago led to a nightlong series of scientific talks to a standing-room audience of physicists at the March 1987 meeting of the American Physical Society, an event that attendees still fondly refer to as the Woodstock of Physics. The enthusiasm about the magnesium boride findings is "less than that, but it's still quite exciting," said Dr. Crabtree, who is organizing a special session on the new superconductors that will be held at the physical society's March meeting in Seattle.