The quantum picture of a detector

M. F. Z. Arruda, Willamys C. Soares, Stephen Patrick Walborn +4 more

The advanced-wave picture is ``... an intuitive treatment of two-photon correlation with the help of the concept of an effective field acting upon one of the two detectors and formed by parametric conversion of the advanced wave emitted by the second detector ...'' [A. V. Belinskii and D. N. Klyshko, Sov. Phys. JETP 78, 259 (1994)]. This quote from Belinskii and Klyshko nicely describes the concept of the advanced-wave picture: an intuitive tool for designing and predicting results from coincidence-based two-photon experiments. Up to now, the advanced-wave picture has been considered primarily for the case of an ideal plane-wave pump beam and only for design purposes. Here we study the advanced-wave picture for a structured pump beam and in the context of stimulated emission provoked by an auxiliary input laser beam. This suggests stimulated parametric down-conversion as a useful experimental tool for testing the experimental sets designed with the advanced-wave picture. We present experimental results demonstrating the strategy of designing the experiment with advanced-wave picture and testing with stimulated emission.

Anonymous

François Chapeau‐Blondeau

Rosalinda Gaudio, Koen op ‘t Hoog, Zili Zhou +2 more

We introduced, characterized and modeled a simple nanodetector to investigate the efficiency and yield limitations of NbN superconducting single photon detectors. These crucial issues are related to the detectors strongly inhomogeneous nature at the nanoscale.

Chandra M. Natarajan, Lijian Zhang, Hendrik B. Coldenstrodt-Ronge +5 more

Superconducting nanowire single-photon detectors (SNSPDs) are widely used in telecom wavelength optical quantum information science applications. Quantum detector tomography allows the positive-operator-valued measure (POVM) of a single-photon detector to be determined. We use an all-fiber telecom wavelength detector tomography test bed to measure detector characteristics with respect to photon flux and polarization, and hence determine the POVM. We study the SNSPD both as a binary detector and in an 8-bin, fiber based, Time-Multiplexed (TM) configuration at repetition rates up to 4 MHz. The corresponding POVMs provide an accurate picture of the photon number resolving capability of the TM-SNSPD.

Masao Osaki