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arXiv · 1102.3070

Dynamics of quantum entanglement in Gaussian open systems

Aurelian Isar
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Abstract

In the framework of the theory of open systems based on completely positive quantum dynamical semigroups, we give a description of the dynamics of entanglement for a system consisting of two uncoupled harmonic oscillators interacting with a thermal environment. Using Peres-Simon necessary and sufficient criterion for separability of two-mode Gaussian states, we describe the evolution of entanglement in terms of the covariance matrix for a Gaussian input state. For some values of the temperature of environment, the state keeps for all times its initial type: separable or entangled. In other cases, entanglement generation, entanglement sudden death or a repeated collapse and revival of entanglement take place. We determine the asymptotic Gaussian maximally entangled mixed states (GMEMS) and their corresponding asymptotic maximal logarithmic negativity.

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Aurelian Isar. 2011-02-15. Dynamics of quantum entanglement in Gaussian open systems. https://doi.org/10.1088/0031-8949%2F82%2F03%2F038116

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