Realization of the kicked atom

The kicked atom is realized experimentally by exposing potassium np Rydberg atoms with n similar to 388 to a sequence of up to 50 half-cycle pulses wh ose duration is much shorter than the classical electron orbital period. Th e Rydberg atom survival probability is observed to have a broad maximum for pulse repetition frequencies near the classical orbital frequency. Compari sons with detailed classical trajectory Monte Carlo simulations show that t his behavior provides an unambiguous signature of dynamical stabilization. The classical simulations further show that the kicked hydrogen atom is, de pending on the pulse repetition frequency, chaotic or characterized by a mi xed phase space with various families of fully stable islands within which the atom is stable against ionization. Signatures of stabilization and chao tic diffusion are also observed in the final bound-state distribution of th e surviving atoms. [S1050-2947(99)07302-3].