title: Quantum dephasing and decay of classical correlation functions in chaotic systems.
abstract: We discuss the dephasing induced by internal classical chaotic motion in the absence of any external environment. To this end an extension of fidelity for mixed states is introduced, which we name allegiance. Such a quantity directly accounts for quantum interference and is measurable in a Ramsey interferometry experiment. We show that in the semiclassical limit the decay of the allegiance is exactly expressed, due to the dephasing, in terms of an appropriate classical correlation function. Our results are derived analytically for the case of a nonlinear driven oscillator and then numerically confirmed for the kicked rotor model.
authors.affiliation: Center for Nonlinear and Complex Systems, Università degli Studi dell'Insubria, Via Valleggio 11, 22100 Como, Italy.
authors.forename: Valentin V
authors.initials: VV
authors.lastname: Sokolov
authors.forename: Giuliano
authors.initials: G
authors.lastname: Benenti
authors.forename: Giulio
authors.initials: G
authors.lastname: Casati