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arXiv · 1110.5442

Complete experimental characterization of a superconducting multiphoton nanodetector

J. J. Renema·G. Frucci·Z. Zhou·F. Mattioli·A. Gaggero·R. Leoni·M. J. A. de Dood·A. Fiore·M. P. van Exter
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Abstract

We present a complete method to characterize multiphoton detectors with a small overall detection efficiency. We do this by separating the nonlinear action of the multiphoton detection event from linear losses in the detector. Such a characterization is a necessary step for quantum information protocols with single and multiphoton detectors and can provide quantitative information to understand the underlying physics of a given detector. This characterization is applied to a superconducting multiphoton nanodetector, consisting of an NbN nanowire with a bowtie-shaped subwavelength constriction. Depending on the bias current, this detector has regimes with single and multiphoton sensitivity. We present the first full experimental characterization of such a detector.

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J. J. Renema, G. Frucci, Z. Zhou, F. Mattioli, A. Gaggero, R. Leoni, M. J. A. de Dood, A. Fiore, M. P. van Exter. 2011-10-25. Complete experimental characterization of a superconducting multiphoton nanodetector. https://arxiv.org/abs/1110.5442

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