arXiv:1301.3337 · Physical Review B
Universal response curve for nanowire superconducting single-photon detectors
J. J. Renema, G. Frucci, Zili Zhou, F. Mattioli, Alessandro Gaggero, Roberto Leoni, M. J. A. de Dood, Andrea Fiore, Martin P. van Exter
Abstract
Using detector tomography, we investigate the detection mechanism in NbN-based superconducting single photon detectors (SSPDs). We demonstrate that the detection probability uniquely depends on a particular linear combination of bias current and energy, for a large variation of bias currents, input energies and detection probabilities, producing a universal detection curve. We obtain this result by studying multiphoton excitations in a nanodetector with a sparsity-based tomographic method that allows factoring out of the optical absorption. We discuss the implication of our model system for the understanding of meander-type SSPDs.