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Updated: Aug 9, 2026

Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Full characterization of a three-photon Greenberger-Horne-Zeilinger state using quantum state tomography
K J Resch1, P Walther, A Zeilinger
1Institut für Experimentalphysik, Universität Wien, Boltzmanngasse 5, 1090 Vienna, Austria.
Abstract:
We have performed the first experimental tomographic reconstruction of a three-photon polarization state. Quantum state tomography is a powerful tool for fully describing the density matrix of a quantum system. We measured 64 three-photon polarization correlations and used a "maximum-likelihood" reconstruction method to reconstruct the Greenberger-Horne-Zeilinger state. The entanglement class has been characterized using an entanglement witness operator and the maximum predicted values for the Mermin inequality were extracted.
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