Number 2, October 4, 1990 by Phillip F. Schewe and Ben Stein
SUPERCONDUCTIVITY at 130 K in a Tl-Sr-V-O compound has been reported by a Hitachi team led by Shin-Pei Matsuda at a meeting in Tokyo on September 19. The vanadium oxide material, which contains no copper, exhibited two critical temperatures, at 30 K and at 130 K, indicating that it has at least two superconducting phases. (High-Tc Update, Oct. 1, 1990; published at Iowa State University; contact John Clem, 515-294-4223)
LASER COOLING DOWN TO MICROKELVIN temperatures is now possible. The lowest kinetic-temperatures ever measured for a sample of atoms using a laser cooling device is 2.5 microkelvins, achieved at the Ecole Normale Superieure with cesium atoms. (Physics Today, October 1990; contact William Phillips at NIST, 301-975-6554)
AMERICAN VACUUM SOCIETY MEETING IN TORONTO (October 8-12): Highlights of this annual national meeting include sessions on biomaterial surfaces, nano engineering, high-temp. superconductivity, and new plasma processing techniques. At a session on silicon-based heterostructures, certain speakers will suggest that SiGe heterostructures may rival their GaAs counterparts in switching speed and may even be light emitting, a fact which would have important implications for opto-electronic applications. (See the "Announcements and News Release section of Pinet for more information. The meeting program chair is Frank Jansen, Xerox, 716-422-8525.)
THE MOST PUBLISHED PHYSICIST OF THE PAST DECADE is Edward Witten of Princeton. Working in particle physics theory, especially on the theory of superstrings, Witten has published more than forty papers each of which has attracted fifty or more citations in other papers. Besides his many physics honors, Witten, who is 39 years old, recently received the Field Medal, the prestigious quadrennial mathematics award. (The Scientist, September 3, 1990)
A NEW FORM OF PURE SOLID CARBON has been discovered by a team of scientists from the Max Planck Institute in Heidelberg (Germany) and the University of Arizona. X-ray diffraction studies have shown that the new solid consists of a "somewhat disordered hexagonal close packing of soccer-ball shaped C60 molecules." The crystallographic name for such an icosohedral shape is "fullerene," after the popular architect Buckminster Fuller, who pioneered the construction of geodesic domes. Spherical viruses and various other objects in nature possess a fullerene structure. The new carbon solid, the discoverers believe, may be usable as lubricants or as a sort of "molecular container" for smaller molecules. (Nature, 27 Oct 90)
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