How to measure squeezing and entanglement of Gaussian states without homodyning
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Updated: Aug 22, 2026

Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Jaromír Fiurásek1, Nicolas J Cerf
1QUIC, Ecole Polytechnique, CP 165, Université Libre de Bruxelles, 1050, Belgium.
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.
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