title: Rapid decoherence in integrable systems: a border effect.
abstract: We show that rapid decoherence, usually associated with chaotic dynamics, is not necessarily a hallmark of nonintegrability: border effects in integrable systems may produce similarly drastic decoherence rates. These can be found when the subsystem under observation possesses an energy limitation as, e.g., in the N-atom Jaynes-Cummings model. We show for this model that special initial coherent wave packets exhibit entropy production rates strikingly similar to the chaotic case. Also, a (de)localization phenomenon is found to be a function of the proximity to the phase-space border.
authors.affiliation: Instituto de Física "Gleb Wataghin," Universidade Estadual de Campinas, 13083-970 Campinas, SP, Brazil.
authors.forename: R M
authors.initials: RM
authors.lastname: Angelo
authors.forename: K
authors.initials: K
authors.lastname: Furuya
authors.forename: M C
authors.initials: MC
authors.lastname: Nemes
authors.forename: G Q
authors.initials: GQ
authors.lastname: Pellegrino