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arXiv:quant-ph/0311119 · Physical Review Letters

How to Measure Squeezing and Entanglement of Gaussian States without Homodyning

Jaromı́r Fiurášek, Nicolas J. Cerf

Published Aug 6, 2004• 71 citations
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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.
DOI
10.1103/physrevlett.93.063601

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