Ancilla-Assisted Calibration of a Measuring Apparatus

作者：Brida G^*; Ciavarella L; Degiovanni I P; Genovese M; Migdall A; Mingolla M G; Paris M G A; Piacentini F; Polyakov S V

来源：Physical Review Letters, 2012, 108(25): 253601.

DOI：10.1103/PhysRevLett.108.253601

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.

• 出版日期2012-6-19