Atomic Earthworms  A group of materials scientists has unleashed
atomic-scale earthworms, which eat meandering trenches just a
few atoms wide through a semiconductor. Spawned when the
researchers mixed two elements in a thin film and let it cool,
the worms might one day serve to mass-produce chip patterns so
tiny that they would alter the quantum behavior of the electrons
they confine. Such "quantum wires" could lead to improved
sensing devices or lasers.  Semiconductor lasers like those in
CD players already exploit quantum mechanics by trapping
electrons in an atoms-thick layer called a quantum well. By the
laws of quantum physics, the close confinement only allows the
electrons a few distinct energy states. Because a laser works by
forcing electrons to jump between energy states, better
confinement translates to a more efficient laser--one that fits
in your living room instead of a physics lab. Now materials
scientists are dreaming of the next step in electron confinement
--quantum wires, which would trap e