Experimental realization of a measurement conditional unitary operation at single photon level and application to detector characterization
Marco Genovese, Brida, G, Chekhova, M, Gramegna, M, Krivitsky, L, Kulik, S, Rastello, M L
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.