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arXiv · 0706.0935

Experimental Measurement of Multi-dimensional Entanglement via Equivalent Symmetric Projection

F. W. Sun·J. M. Cai·J. S. Xu·G. Chen·B. H. Liu·C. F. Li·Z. W. Zhou·G. C. Guo
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Abstract

We construct a linear optics measurement process to determine the entanglement measure, named \emph{I-concurrence}, of a set of $4 \times 4$ dimensional two-photon entangled pure states produced in the optical parametric down conversion process. In our experiment, an \emph{equivalent} symmetric projection for the two-fold copy of single subsystem (presented by L. Aolita and F. Mintert, Phys. Rev. Lett. \textbf{97}, 050501 (2006)) can be realized by observing the one-side two-photon coincidence without any triggering detection on the other subsystem. Here, for the first time, we realize the measurement for entanglement contained in bi-photon pure states by taking advantage of the indistinguishability and the bunching effect of photons. Our method can determine the \emph{I-concurrence} of generic high dimensional bipartite pure states produced in parametric down conversion process.

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F. W. Sun, J. M. Cai, J. S. Xu, G. Chen, B. H. Liu, C. F. Li, Z. W. Zhou, G. C. Guo. 2007-11-20. Experimental Measurement of Multi-dimensional Entanglement via Equivalent Symmetric Projection. https://doi.org/10.1103/physreva.76.052303

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