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Full characterization of a three-photon GHZ state using quantum state tomography

Kevin J. Resch·Philip Walther·Anton Zeilinger
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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 GHZ state. The entanglement class has been characterized using an entanglement witness operator and the maximum predicted values for the Mermin inequality was extracted.

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Kevin J. Resch, Philip Walther, Anton Zeilinger. 2004-12-20. Full characterization of a three-photon GHZ state using quantum state tomography. https://doi.org/10.1103/physrevlett.94.070402

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