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arXiv · 0711.3477

Gaussian entanglement of symmetric two-mode Gaussian states

Paulina Marian·Tudor A. Marian
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Abstract

A Gaussian degree of entanglement for a symmetric two-mode Gaussian state can be defined as its distance to the set of all separable two-mode Gaussian states. The principal property that enables us to evaluate both Bures distance and relative entropy between symmetric two-mode Gaussian states is the diagonalization of their covariance matrices under the same beam-splitter transformation. The multiplicativity property of the Uhlmann fidelity and the additivity of the relative entropy allow one to finally deal with a single-mode optimization problem in both cases. We find that only the Bures-distance Gaussian entanglement is consistent with the exact entanglement of formation.

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Paulina Marian, Tudor A. Marian. 2007-11-21. Gaussian entanglement of symmetric two-mode Gaussian states. https://doi.org/10.1140/epjst%2Fe2008-00731-x

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