Discovery may earn billions, Nobel for UH
CARLOS BYARS, Houston Chronicle Science Writer Staff
MON 02/16/1987 HOUSTON CHRONICLE, Section 1, Page 1, 2 STAR Edition
Researchers at the University of Houston have grasped the Holy Grail of low-temperature physics, surpassing in a few months of intense work a goal long believed to be totally out of reach. Their discovery of a superconductor that works at a temperature higher than liquid nitrogen could revolutionize the electrical industry, earn a Nobel Prize and be worth billions to the university. Paul Chu, head of a team working to create new superconductors - materials that conduct electricity without resistance - said the new material operates at 98 degrees Kelvin. This is well above the critical 77-degree temperature of liquid nitrogen. This temperature, though low by human standards at minus 367 degrees Fahrenheit, is more than high enough to allow the use of cheap, readily available liquid nitrogen as a coolant. Previously, the temperatures required for superconductivity could be achieved only by using much scarcer liquid helium, virtually precluding any possibility of widespread commercial use of superconductors. The discovery holds the promise of major advances in the transmission and use of electrical power, including better detectors of low-level heat and radio signals, more powerful magnets and motors and new tools for medicine. Chu's discovery was announced here and in a scientific paper accepted for publication by Physical Review Letters, considered the most important journal of physics. This was the fourth major increase in the temperature of superconductivity in the last three months, after 13 years without a breakthrough in the field. The discovery appears to have put Chu and the University of Houston far ahead of several well-funded, highly competitive teams. At stake is more than the intense competition for scientific honors and awards. The organization that wins clear title to the basic patents stands to gain license fees amounting to billions of dollars. Sharing credit for the discovery was M.K. Wu of the University of Alabama, who was listed as co-author with Chu of a separate paper in the same publication announcing a superconductor at 93 degrees Kelvin. Wu is one of Chu's former students. Further advances are expected. Roy Weinstein, UH dean of natural science and mathematics, said the group has seen signs that superconductivity occurs above 148 degrees Kelvin (minus 312 degrees F.), and very preliminary results hint that Chu's line of research may result in superconductivity at or near room temperature. Such an astounding development has not previously been considered even a possibility by researchers in the field of low-temperature physics. Chu's group includes P.H. Hor, R.L. Meng, L. Gao, Z.J. Huang and Y.Q. Wang of the University of Houston and Wu and J.R. Ashburn of the University of Alabama at Huntsville. They are in hot competition with other researchers including groups at AT&T Bell Labs, University of Tokyo, Argonne National Laboratory, IBM, Los Alamos National Laboratory and Stanford University. Weinstein says the competition involves three major issues: The discovery at an International Business Machines Corp. lab in Zurich, Switzerland, of the combination of chemicals used to make the superconductor; the actual production of a superconductor from that material, which was first achieved at the University of Houston; and most important, Chu's discovery of the role of pressure in superconductivity, now called the "Chu effect." "IBM-Zurich found some promising material. They didn't know how to make it a superconductor or how to vary it to get a superconductor, but they did get everybody started in the right direction," Weinstein said. "Paul is the leader in developing new techniques for making the superconductor material." "There is some hope that Chu will get a Nobel Prize out of this," Weinstein added. "If he does, it will be for discovering the role of pressure." Before Chu's discovery, pressure was not thought to have any effect on superconducting materials. But Chu found that the superconductivity temperature rises when the new materials are squeezed under high pressure. Weinstein said this was Chu's key clue that he was dealing with something new. But pressure is not needed to build the material, he added. "When you apply pressure you reduce the spacing between the individual parts of the molecules. What's important is to close up the internal spaces. This can be done by filling in those spaces with smaller atoms. You don't have to use pressure. You use a different approach," Weinstein said. One different approach is to replace one of the ingredients with another that is physically smaller. The original mixture suggested by IBM was lanthanum, barium, copper and oxygen (copper oxide). Chu now is working with strontium instead of barium or yttrium instead of lanthanum. Weinstein says the Chu effect has revealed a whole new group of substances which are, or may be, superconductors. Another way to reduce the spaces is to lay the superconducting material a few atoms at a time on a fine crystalline base material. As the atoms are deposited on the base, they tend to line up in the same tightly packed arrangement as the crystals of the base, thus reducing the spaces. "If Paul had a hundred Ph.D.s he could keep them all working on different systems," Weinstein said. Weinstein said the university has applied for a patent on Chu's discoveries, claiming a huge variety of chemicals and processes to make superconductors.
But the secret to prodigious wealth is to turn the material into a wire. "If we can't make a wire it will be a very fine discovery but not much money," he said. |
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