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Updated: May 8, 2025

Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
An operational distinction between quantum entanglement and classical non-separability
Natalia Korolkova1,2, Luis Sánchez-Soto2,3, Gerd Leuchs2,4,5
1School of Physics and Astronomy, University of St. Andrews, North Haugh, St. Andrews, Fife KY16 9SS, UK.
Abstract:
Quantum entanglement describes superposition states in multi-dimensional systems-at least two partite-which cannot be factorized and are thus non-separable. Non-separable states also exist in classical theories involving vector spaces. In both cases, it is possible to violate a Bell-like inequality. This has led to controversial discussions, which we resolve by identifying an operational distinction between the classical and quantum cases.This article is part of the theme issue 'The quantum theory of light'.
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