Quantum phase lock in Rydberg atoms

We discuss localized quantum states that correspond to classical phase lock in a Rydberg atom dressed by a resonant, Circularly Polarized (CP) microwa ve field. These quantum states can either be localized along certain classi cal trajectories or form fully localized, quasi-Gaussian wave packets. We a lso demonstrate that, by manipulating these localized states, it is possibl e to control effectively, and for a range of energies and angular momenta, the population of the eigenstates of a field-free Rydberg atom.