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arXiv · 1607.03088

Probing the Hotspot Interaction Length in NbN Nanowire Superconducting Single-Photon Detectors

J. J. Renema·R. Gaudio·Q. Wang·M. P. van Exter·A. Fiore·M. J. A. de Dood
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Abstract

We measure the maximal distance at which two absorbed photons can jointly trigger a detection event in NbN nanowire superconducting single photon detector (SSPD) microbridges by comparing the one-photon and two-photon efficiency of bridges of different overall lengths, from 0 to 400 nm. We find a length of $23 \pm 2$ nm. This value is in good agreement with to size of the quasiparticle cloud at the time of the detection event.

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J. J. Renema, R. Gaudio, Q. Wang, M. P. van Exter, A. Fiore, M. J. A. de Dood. 2016-07-11. Probing the Hotspot Interaction Length in NbN Nanowire Superconducting Single-Photon Detectors. https://doi.org/10.1063/1.4984816

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