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All possible bipartite positive-operator-value measurements of two-photon polarization states

S. E. Ahnert·M. C. Payne
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Abstract

Here we propose an implementation of all possible Positive Operator Value Measures (POVMs) of two-photon polarization states. POVMs are the most general class of quantum measurements. Our setup requires linear optics, Bell State measurements and an entangled three-photon ancilla state, which can be prepared separately and in advance (or 'off-line'). As an example we give the detailed settings for a simultaneous measurement of all four Bell States for an arbitrary two-photon polarization state, which is impossible with linear optics alone.

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S. E. Ahnert, M. C. Payne. 2005-12-24. All possible bipartite positive-operator-value measurements of two-photon polarization states. https://doi.org/10.1103/physreva.73.022333

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