title: A generalized fidelity amplitude for open systems.
abstract: We consider a central system which is coupled via dephasing to an open system, i.e. an intermediate system which in turn is coupled to another environment. Considering the intermediate and far environment as one composite system, the coherences in the central system are given in the form of fidelity amplitudes for a certain perturbed echo dynamics in the composite environment. On the basis of the Born-Markov approximation, we derive a master equation for the reduction of that dynamics to the intermediate system alone. In distinction to an earlier paper (Moreno et al 2015 Phys. Rev. A 92, 030104. (doi:10.1103/PhysRevA.92.030104)), where we discussed the stabilizing effect of the far environment on the decoherence in the central system, we focus here on the possibility of using the measurable coherences in the central system for probing the open quantum dynamics in the intermediate system. We illustrate our results for the case of chaotic dynamics in the near environment, where we compare random matrix simulations with our analytical result.
authors.affiliation: Departamento de Física, Universidad de Guadalajara, Guadalajara, Jalísco, México thomas.gorin@cucei.udg.mx.
authors.forename: T
authors.identifier: http://orcid.org/0000-0003-4993-2135
authors.initials: T
authors.lastname: Gorin
authors.affiliation: Centro de Investigación en Ciencias, Universidad Autońoma del Estado de Morelos, Cuernavaca, Morelos, México Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México.
authors.forename: H J
authors.initials: HJ
authors.lastname: Moreno
authors.affiliation: Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México Centro Internacional de Ciencias A.C., Cuernavaca, Morelos, México.
authors.forename: T H
authors.initials: TH
authors.lastname: Seligman
keywords: fidelity; master equation; open quantum system; quantum Loschmidt echo; random matrix theory