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Experimental realization of a measurement conditional unitary operation at single photon level and application to detector characterization

M. Genovese·G. Brida·M. Chekhova·M. Gramegna·L. Krivitsky·S. Kulik·M. L. Rastello
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Abstract

Our last experimental results on the realization of a measurement-conditional unitary operation at single photon level are presented. This gate operates by rotating by $90^o$ the polarization of a photon produced by means of Type-II Parametric Down Conversion conditional to a polarization measurement on the correlated photon. We then propose a new scheme for measuring the quantum efficiency of a single photon detection apparatus by using this set-up. We present experimental results obtained with this scheme compared with {\it traditional} biphoton calibration. Our results show the interesting potentiality of the suggested scheme.

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M. Genovese, G. Brida, M. Chekhova, M. Gramegna, L. Krivitsky, S. Kulik, M. L. Rastello. 2004-09-09. Experimental realization of a measurement conditional unitary operation at single photon level and application to detector characterization. https://doi.org/10.1117/12.561416

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