ON MASTER-EQUATIONS, SPECTRAL RESOLUTIONS, AND SELF-ENERGY FIELDS IN PROPAGATOR THEORIES FOR QUANTUM OPEN SYSTEMS

Master equations for propagators in quantum open systems and their spectral resolutions are derived. The Zwanzig partitioning scheme along the superoperator algebra are used to derive equations of motion for partitioned operators in a Liouville space. The reservoir influence on the dynamical evolution of operators is shown to lead explicitly to dissipative effects arising from memory terms in the evolution equations of such operators. It is also shown that spectral representations may be written in a self-consistent analytic way by means of the self-energy fields for transition energies of the system by taking into account the lack of the complete knowledge about the reservoir. A kinematic fluid interpretation of the resultant equations is given and an explicit form of the ''collision'' superoperator is obtained. Finally, a simple example to illustrate the determination of self-energy fields for the system-reservoir interaction corrections is given. (C) 1995 John Wiley & Sons, Inc.