Number 266 (Story #1), April 12, 1996 by Phillip F. Schewe and Ben Stein TAILOR-MADE QUANTUM STATES OF MOTION for a single ion in a trap have been created and observed for the first time. The quantized vibrations of atoms in molecules have been previously observed, but never before have physicists deliberately engineered quantum states of motion in a single atom. Trapping a single beryllium ion in the electric fields of a device known as a Paul trap, Dawn Meekhof (meekhof@boulder.nist.gov) and her colleagues at NIST-Boulder first caught the atom at the center of the trap, where it was free to move in three dimensions. Then they laser-cooled the ion to its lowest-energy state, eliminating the thermal noise that could otherwise obscure signatures of the quantum states the team sought to create. Finally, from the lowest-energy state, the researchers used other lasers to create numerous quantum states specifying the overall motion of the ion. The scientists hope that these and other quantum motional states will provide textbook demonstrations of basic concepts in quantum physics. In a separate experiment, Serge Haroche (haroche@physique.ens.fr) and his colleagues at the Ecole Normale Superieure in France produced the most direct evidence yet of the quantum nature of light by studying how rubidium atoms inside a cavity exchange bundles of energy with a microwave field. (D.M. Meekhof et al. and M. Brune et al., Phys. Rev. Lett., 11 March 1996; for more information, see Science, 5 April 1996; Nature, 4 April 1996; Physics News Update #250)