Number 245 (Story #2), October 18, 1995 by Phillip F. Schewe and Ben Stein ATOMS HAVE BEEN GUIDED THROUGH HOLLOW OPTICAL FIBERS , introducing a potentially convenient and flexible method for manipulating atoms and perhaps measuring their wavelike properties. Taking a hollow glass fiber and filling it with laser light, a Colorado group (including Dana Anderson and Eric Cornell, 303-492-6281) has steered rubidium atoms through the twists and turns of fibers with cores as narrow as 10 microns. By making the laser light brightest at the center of the core, and tuning the laser just below the frequency at which the atoms absorb the maximum amount of light, the researchers ensure that the atoms are attracted to the core's center region as they travel through the fiber. This technique will be useful for moving atoms from a high-density source into an ultra-high vacuum environment in atom physics experiments. It might be possible to make atom-scale electronic circuits by performing "lithography in reverse": instead of using chemicals to etch away features on a silicon wafer, one would use the fiber as an "atomic fountain pen" to spray atoms onto the surface. There is also the possibility of performing "fiber-atom interferometry." If the atoms are cold enough and the fiber narrow enough so that the atom's wavelength is comparable to the diameter of the fiber, it will act as an atom wave. By splitting the fiber in two, the atom would split into a pair of wavelets which could be later recombined to produce an interference pattern. (M.J. Renn et al, 30 October 1995, Phys. Rev. Lett.; journalists can obtain text and figures from AIP Public Information, physnews@aip.org)