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arXiv:quant-ph/0412151 · Physical Review Letters

Full Characterization of a Three-Photon Greenberger-Horne-Zeilinger State Using Quantum State Tomography

Kevin J. Resch, Philip John Walther, Anton Zeilinger

Published Feb 24, 2005• 125 citations
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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.

DOI
10.1103/physrevlett.94.070402

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