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arXiv · quant-ph/0310087

Entanglement and purity of two-mode Gaussian states in noisy channels

Alessio Serafini·Fabrizio Illuminati·Matteo G. A. Paris·Silvio De Siena
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Abstract

We study the evolution of purity, entanglement and total correlations of general two--mode Gaussian states of continuous variable systems in arbitrary uncorrelated Gaussian environments. The time evolution of purity, Von Neumann entropy, logarithmic negativity and mutual information is analyzed for a wide range of initial conditions. In general, we find that a local squeezing of the bath leads to a faster degradation of purity and entanglement, while it can help to preserve the mutual information between the modes.

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Alessio Serafini, Fabrizio Illuminati, Matteo G. A. Paris, Silvio De Siena. 2004-02-27. Entanglement and purity of two-mode Gaussian states in noisy channels. https://doi.org/10.1103/physreva.69.022318

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