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Lower bounds on the entanglement of formation for general Gaussian states

G. Rigolin·C. O. Escobar
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Abstract

We derive two lower bounds on entanglement of formation for arbitrary mixed Gaussian states by two distinct methods. To achieve the first one we use a local measurement procedure derived by Giedke et al [Quantum Inf. and Comp. vol.1, 79 (2001)] that symmetrizes a general Gaussian state and the fact that entanglement cannot increase under local operations and classical communications. The second one is obtained via a generalization to mixed states of an interesting result derived by Giedke et al [quant-ph/0304042], who show that squeezed states are those that, for a fixed amount of entanglement, maximize Einstein-Podolsky-Rosen-like correlations.

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G. Rigolin, C. O. Escobar. 2004-01-18. Lower bounds on the entanglement of formation for general Gaussian states. https://doi.org/10.1103/physreva.69.012307

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