Decoherence and asymptotic entanglement in open quantum dynamics

Content Provider	Semantic Scholar
Author	Isar, Aurelian
Abstract	In the framework of the theory of open systems based on completely positive quantum dynamical semigroups, we determine the degree of quantum decoher-ence of a harmonic oscillator interacting with a thermal bath. It is found that the system manifests a quantum decoherence which is more and more significant in time. We also calculate the decoherence time and show that it has the same scale as the time after which thermal fluctuations become comparable with quantum fluctuations. Then we solve the master equation for two independent harmonic oscillators interacting with an environment in the asymptotic long-time regime. We give a description of the continuous-variable asymptotic entanglement in terms of the covariance matrix of the quantum states of the considered system for an arbitrary Gaussian input state. Using the Peres–Simon necessary and sufficient condition for separability of two-mode Gaussian states, we show that the two non-interacting systems immersed in a common environment become asymptotically entangled for certain environments, so that in the long-time regime they manifest non-local quantum correlations.
File Format	PDF HTM / HTML
Alternate Webpage(s)	http://arxiv.org/pdf/0803.3682v1.pdf
Language	English
Access Restriction	Open
Subject Keyword	Arabic numeral 0 Asymptote Class Coefficient Dynamical system Existential quantification Information processing Interaction Lindblad equation Linear separability Normal Statistical Distribution Open quantum system Oscillator Device Component Peres–Horodecki criterion Population Parameter Quantum decoherence Quantum dot Quantum dynamics Quantum entanglement Quantum fluctuation Quantum information science Quantum state
Content Type	Text
Resource Type	Article