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arXiv · 0808.3325

Shannon dimensionality of quantum channels and its application to photon entanglement

J. B. Pors·S. S. R. Oemrawsingh·A. Aiello·M. P. van Exter·E. R. Eliel·G. W. 't Hooft·J. P. Woerdman
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Abstract

We introduce the concept of Shannon dimensionality D as a new way to quantify bipartite entanglement as measured in an experiment. This is applied to orbital-angular-momentum entanglement of two photons, using two state analyzers composed of a rotatable angular-sector phase plate that is lens-coupled to a single-mode fiber. We can deduce the value of D directly from the observed two-photon coincidence fringe. In our experiment, D varies between 2 and 6, depending on the experimental conditions. We predict how the Shannon dimensionality evolves when the number of angular sectors imprinted in the phase plate is increased and anticipate that D = 50 is experimentally within reach.

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J. B. Pors, S. S. R. Oemrawsingh, A. Aiello, M. P. van Exter, E. R. Eliel, G. W. 't Hooft, J. P. Woerdman. 2008-08-25. Shannon dimensionality of quantum channels and its application to photon entanglement. https://doi.org/10.1103/physrevlett.101.120502

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