title: Decoherence and quantum-classical dynamics in a dissipative bath.
abstract: The dynamics of a mixed quantum-classical system, in which the classical subsystem interacts with a dissipative bath, is investigated. This description of the dynamics will be appropriate if the details of the bath dynamics are unimportant but its presence plays an important role in the dissipation of energy to the environment. In this dynamical description, which can be simulated employing an ensemble of stochastic surface-hopping trajectories, the strength of the dissipation is controlled by a friction coefficient. We show that if decoherence, whose effects are controlled by the bath friction, is sufficiently rapid, the equation of motion can be reduced to a master equation. Thus, decoherence and the validity of master equation models may be explored as a function of bath friction. We use this framework to study the mechanism of decoherence in a simple model nonadiabatic chemical reaction.
authors.affiliation: Department of Chemistry, Chemical Physics Theory Group, University of Toronto, Toronto, Ontario M5S 3H6, Canada. jprank@chem.utoronto.ca
authors.forename: J P
authors.initials: JP
authors.lastname: Rank
authors.forename: Raymond
authors.initials: R
authors.lastname: Kapral