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arXiv · 1205.0798

Ancilla-Assisted Calibration of a Measuring Apparatus

G. Brida·L. Ciavarella·I. P. Degiovanni·M. Genovese·A. Migdall·M. G. Mingolla·M. G. A. Paris·F. Piacentini·S. V. Polyakov
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Abstract

A quantum measurement can be described by a set of matrices, one for each possible outcome, which represents the positive operator-valued measure (POVM) of the sensor. Efficient protocols of POVM extraction for arbitrary sensors are required. We present the first experimental POVM reconstruction that takes explicit advantage of a quantum resource, i.e., nonclassical correlations with an ancillary state. A POVM of a photon-number-resolving detector is reconstructed by using strong quantum correlations of twin beams generated by parametric down-conversion. Our reconstruction method is more statistically robust than POVM reconstruction methods that use classical input states.

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G. Brida, L. Ciavarella, I. P. Degiovanni, M. Genovese, A. Migdall, M. G. Mingolla, M. G. A. Paris, F. Piacentini, S. V. Polyakov. 2012-05-03. Ancilla-Assisted Calibration of a Measuring Apparatus. https://doi.org/10.1103/physrevlett.108.253601

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