title: Quantum Poincare recurrences for a hydrogen atom in a microwave field
abstract: We study the time dependence of the ionization probability of Rydberg atoms driven by a microwave field, both in classical and in quantum mechanics. The quantum survival probability follows the classical one up to the Heisenberg time and then decays algebraically as P(t) approximately 1/t. This decay law derives from the exponentially long times required to escape from some region of the phase space, due to tunneling and localization effects. We also provide parameter values which should allow one to observe such decay in laboratory experiments.
authors.affiliation: Service de Physique de l'Etat Condense, Centre d'Etudes de Saclay, F-91191 Gif-sur-Yvette, France.
authors.initials: G
authors.lastname: Benenti
authors.initials: G
authors.lastname: Casati
authors.initials: G
authors.lastname: Maspero
authors.initials: DL
authors.lastname: Shepelyansky