Capturing the motion of magnetic vortices.Applying a new imaging technique, researchers in Japan have for the first time directly observed the movement of tiny whirlpools of magnetism trapped in a superconducting material. Their observations help settle a long-standing debate concerning the behavior of these vortices vor·ti·ces n. A plural of vortex. as the temperature of an oxide superconductor A material that has little resistance to the flow of electricity. Traditional superconductors operate at absolute zero (-459.67 degrees Fahrenheit or -273.15 degrees Celsius). Experiments in the 1980s raised the temperature to -321 degrees Fahrenheit. -- placed in a magetic field -- is varied. Akira Tonomura and his co-workers at the Advanced Research Laboratory of Hitachi, Ltd. in Saitama, Japan, report their findings in the Nov. 15 PHYSICAL REVIEW LETTERS Physical Review Letters is one of the most prestigious journals in physics.[1] Since 1958, it has been published by the American Physical Society as an outgrowth of The Physical Review. . "To those in the superconductivity superconductivity, abnormally high electrical conductivity of certain substances. The phenomenon was discovered in 1911 by Kamerlingh Onnes, who found that the resistance of mercury dropped suddenly to zero at a temperature of about 4.2°K;. business, these images are nothing less than specatcular," comments David J David J. Haskins (b. April 24, 1957, in Northampton, England) is a British alternative rock musician. He was the bassist for the seminal gothic rock band Bauhaus. Life and work . Bishop of AT&T Bell Laboratories in Murray Hill, N.J., in the Nov. 18 NATURE. "It is a truly outstanding piece of experimental physics." A superconductor normally shields itself from the effects of magnetic fields magnetic fields, n.pl the spaces in which magnetic forces are detectable; created by magnetostrictive ultrasonic scalers to cause the tips of instruments such as ultrasonic scalers to vibrate. in which it is placed by preventing such fields from penetrating its interior. For oxide superconductors, however, once this external magnetic field exceeds a certain value, it begins to enter the material. This penetrating magnetic field exists within the superconductor in the form of separate vortices -- whirlpools of electric current. At low temperatures, the vortices arrange themselves into a distinctive pattern, of lattice. The behavior of these vortices has a great influence on how well a superconductor carries electricity, particularly at high currents, when the vortices get in the way. But researchers have been unsure whether a vortex lattice remains intact below a certain temperature and "melts" into disarray above this temperature (SN: 4/189, p.197). The Hitachi team confirmed that at low temperatures, the vortices form a lattice. As the researchers raised the temperature, the vortices moved a little with each temperature step but eventually settled again into a stationary pattern. However, once a certain temperature -- a critical point -- was reached, the lattice melted. A previous result indicated vortices start moving well below this temperature. "Many of us have been consumed for the past six years by the issue of whether magnetic flux lattices could indeed melt," Bishop sasy. Now, "seeing is believing Seeing is believing is an idiom first recorded in this form in 1639 that means "only physical or concrete evidence is convincing".[1] Seeing is Believing may refer to:
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