Selective Excitation of Dressed Atomic States by Use of Phase-Controlled Optical Fields

We have studied the response of atoms in a dilute collimated atomic beam to transient phase-controlled resonant excitation fields. We demonstrate that the use of such excitation makes it possible to place the atoms into stationary states of the coupled atom-field system. We show that these states, which are easily visualized in the two-level-atom vector model, are equivalent to the dressed states of resonance fluorescence theory. Studies of atoms in pure dressed states should allow interesting tests of basic atom-field interactions.