Word: physicist
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From the time that Dutch Physicist Heike Kamerlingh Onnes discovered superconductivity in 1911 until the recent rash of breakthroughs, there was only one way to produce the phenomenon: by bathing the appropriate metals -- and later, certain metallic alloys -- in liquid helium. This exotic substance is produced by lowering the temperature of rare and costly helium gas to 4.2 K (-452 degrees F), at which point it liquefies. But the process is expensive and requires considerable energy. Furthermore, unless the liquid helium is tightly sealed in a heavily insulated container, it quickly warms and vaporizes away. Thus the practical...
Success and celebrity have been a long time in coming to the field of superconductivity. "Until recently," says John Ketterson, a physicist at Northwestern University, "people were glum. There hadn't been a breakthrough in a long time. Funding was drying up. This has sent everyone back into the field with a new burst of enthusiasm." Although Kamerlingh Onnes envisioned early on that his discovery might pave the way for extremely powerful, compact electromagnets, he and other experimenters were stymied by a strange phenomenon: as soon as enough current was flowing through the then known superconductors (lead, tin and mercury...
That was the situation in 1983 when Karl Alex Muller, a physicist at the IBM Zurich Research Laboratory in Switzerland, decided to pursue an approach to superconductivity that had met with limited success in the past. Instead of using the kind of metallic alloys that held the existing record, he turned his attention to the metallic oxides (compounds of metals and oxygen) known as ceramics. Some theorists had suggested ceramics as potential superconductors even though they were poor conductors at room temperatures. In fact, ceramics are often used as insulators-for example, on high-voltage electric- transmission lines...
...Muller had anticipated, other physicists were skeptical. For one thing, the IBM scientists had lacked the sensitive equipment to test for the Meissner effect, the surest proof of superconductivity, and thus could not confirm it in their report. More important, in a field where improvements of a few degrees were reason for celebration, this great a temperature leap seemed unlikely. Douglas Finnemore, a physicist at Iowa State University, admits that he was among the doubters. "Our group read the paper," he says. "We held a meeting and decided there was nothing...
...University of Illinois, Physicist Donald Ginsberg raced out to buy an air mattress and an alarm clock, anticipating a spate of all-nighters. At IBM's Almaden Research Center in San Jose, scientists successfully duplicated the compound, analyzed its crystal structure and passed the information on to the company's labs in Yorktown Heights, N.Y., where their colleagues were able to make thin films of the substance literally overnight. At the University of California, Berkeley, a group that included Theoretical Physicist Marvin Cohen, who had been among those predicting superconductivity in the oxides two decades ago, reproduced...