Interference of light with localized atomic wave functions

The quantized center-of-mass motion of a cold atom confined in a trap poten tial may significantly affect the interaction of the atom with laser light. When the extension of the atomic wave function is of the order of the lase r wavelength, interference effects between the matter and light waves play an important role. Destructive interference may occur for appropriately cho sen motional excitations of the atom, and it leads to a decoupling of the a tom from the driving laser fields. The effects of such destructive interfer ences on the laser-assisted dynamics of the motional quantum state are cons idered for various resonance conditions of the driving lasers, leading to K err-type dynamics, nonlinear coherent displacements, and nonlinear squeezin g.