BUILDING AN ATOM TRAP

摘要

"We created a method to control individual atoms, to get them exactly where we want them, when we want them: an atom trap. Atoms are very fast, so we use powerful cooling lasers to slow them down. The lasers are on a table floating on air cushions, in a room without windows so we can't harm people on the street. We need laser beams coming from all directions so there's a force on the atom opposite its motion regardless of which direction it's moving. It's like a bicyclist's nightmare: Whichever way you go, the wind is against you. Because an atom is so small, light can bring it from moving at the speed of sound to complete rest over about half a meter [about 1.6 feet].