By Peter Weiss
Like a tiny cartoon superhero taking on a huge bully, a photon grabs a passing atom and whirls it in erratic loops.
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Experiments using a new device that creates this action scene demonstrate for the first time that a single photon can trap and control an atom, says Christina J. Hood of the California Institute of Technology in Pasadena. The device permits only one photon at any time, on average, into a minuscule cavity between two small mirrors.