How to Measure Squeezing and Entanglement of Gaussian States without Homodyning
Jaromír Fiurášek,Nicolas J. Cerf +1 more
TLDR
This work proposes a scheme for measuring the squeezing, purity, and entanglement of Gaussian states of light that does not require homodyne detection and needs only beam splitters and single-photon detectors.Abstract:
We propose a scheme for measuring the squeezing, purity, and entanglement of Gaussian states of light that does not require homodyne detection. The suggested setup needs only beam splitters and single-photon detectors. Two-mode entanglement can be detected from coincidences between photodetectors placed on the two beams.read more
Citations
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Entanglement in continuous-variable systems: recent advances and current perspectives
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Extremal entanglement and mixedness in continuous variable systems
TL;DR: The concept of average logarithmic negativity is introduced, showing that it allows a reliable quantitative estimate of continuo us variable entanglement by direct measurements of global and marginal generalized p-entropies.
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Computable measure of nonclassicality for light.
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Gaussian measures of entanglement versus negativities: Ordering of two-mode Gaussian states
TL;DR: Gaussian measures and negativities are definitely inequivalent measures of entanglement on nonsymmetric two-mode Gaussian states, even when restricted to a class of extremal states, and some strong evidence is provided suggesting that they are as well bounded from above as they are shown to be.
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