Floquet analysis of the dynamical stabilization of the kicked hydrogen atom

We analyze the quantum dynamics of the one-dimensional periodically kicked Rydberg atom. The time-dependent Schrodinger equation is solved by employin g a nonunitary representation of the period-one evolution operator in a fin ite basis set that accounts for the outbound probability flux. We find a di rect correspondence between stable classical islands in phase space and the quantum Husimi distributions of stable Floquet states. These results expla in the pronounced peak recently found experimentally in the frequency-depen dent survival probability of Rydberg states subject to a sequence of half-c ycle pulses. [S1050-2947 (99)50605-9].