  The qualitative nature (i.e. integrable vs. chaotic) of the translational
dynamics of a three-level atom in an optical lattice is shown to be
controllable by varying the relative laser phase of two standing wave lasers.
Control is explained in terms of the nonadiabatic transition between optical
potentials and the corresponding regular to chaotic transition in mixed
classical-quantum dynamics. The results are of interest to both areas of
coherent control and quantum chaos.

Quantum Physics;Chaotic Dynamics