Number 31, April 26, 1991 by Phillip F. Schewe and Ben Stein
BUCKYBALLS ARE SUPERCONDUCTING. Arthur F. Hebard (201-582-4944) of AT&T Bell Labs said at a recent meeting of the American Chemical Society in Atlanta (and in the 18 April issue of Nature) that films of carbon-60, doped with potassium, become superconducting at a temperature of 18 K. Indeed doping C-60 seems to be easy. Richard Smalley of Rice University has been able to replace a few carbon atoms in the molecules' soccerball structure with boron and nitrogen atoms; the result he calls "dopyballs." According to Fred Wudl of UC Santa Barbara, "It's a starting material for making a whole new family of organic compounds." (Science News 20 April 1991.)
A DARK SUPERMASSIVE OBJECT has been found in the galaxy NGC6240. The mass of the object, inferred from the rotational motion of the galaxy (a galaxy which seems to be actually two galaxies in collision), is between 40 and 200 billion times that of the Sun. The Rice-Maryland-Hawaii team that made the discovery (reported in the 10 April Astrophysical Journal Letters) have speculated that the object might be a black hole (and if so, the biggest black hole in the universe) or possibly an accumulation of brown dwarfs or neutron stars. (New Scientist, 20 April 1991.)
SQUEEZED SOLITONS may someday facilitate nearly error-free data transmission at bit rates of 10 Gbits per second or more. Solitons, waves that can propagate long distances (in some tests, more than 10,000 km) without changing their shape, may soon be used in optical fiber communications across the Pacific. But solitons, if properly "squeezed," may also be useful for high-speed transmissions over short distances, in computers, for instance. In the squeezed-light phenomenon, the passing of light waves through a nonlinear optical medium can result in a lowering of the quantum noise of one observable (say, the peak intensity, which is related to the light's amplitude) at the expense of an increase in the quantum noise of the conjugate observable, in this case the wave's phase. The squeezed observable can therefore carry information at a lowered error-rate. Tests by Michael Rosenbluth and Robert Shelby (408-927-2423) at IBM Almaden using 200-fs soliton pulses have demonstrated (Physical Review Letters, 14 Jan. 1991) a noise reduction of 32% below the "shot noise," the lowest possible noise normally allowed by quantum mechanics. Higher noise reductions have been achieved in previous squeezing experiments, but not with solitons and not in optical fibers. Even greater levels of noise reduction are theoretically possible with the soliton approach. (Physics World, April 1991.)
NATIONAL PHYSICS DATABASE. The American Physical Society (APS) task force on electronic information systems has recommended that the Society adopt as a long-term goal the creation of a National Physics Database, which in turn would be "the first step toward integrating all the world's scientific literature into an electronic information system." The APS journal Physical Review began accepting submissions in electronic form in 1979 (at first on magnetic tape) and now encourages the use of electronic networks, such as Bitnet, for transmitting articles and referee reports. (Bulletin of the APS, April 1991.)
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