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arXiv · 1210.5395

Temperature-dependence of detection efficiency in NbN and TaN SNSPD

Andreas Engel·Kevin Inderbitzin·Andreas Schilling·Robert Lusche·Alexei Semenov·Heinz-Wilhelm Hübers·Dagmar Henrich·Matthias Hofherr·Konstantin Il'in·Michael Siegel
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Abstract

We present systematic measurements of the temperature-dependence of detection efficiencies in TaN and NbN superconducting nanowire single-photon detectors. We have observed a clear increase of the cut-off wavelength with decreasing temperature that we can qualitatively describe with a temperature-dependent diffusion coefficient of the quasi-particles created after photon absorption. Furthermore, the detection efficiency at wavelengths shorter than the cut-off wavelength as well as at longer wavelengths exhibit distinct temperature dependencies. The underlying causes and possible consequences for microscopic detection models are discussed.

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Andreas Engel, Kevin Inderbitzin, Andreas Schilling, Robert Lusche, Alexei Semenov, Heinz-Wilhelm Hübers, Dagmar Henrich, Matthias Hofherr, Konstantin Il'in, Michael Siegel. 2013-01-08. Temperature-dependence of detection efficiency in NbN and TaN SNSPD. https://doi.org/10.1109/tasc.2013.2239345

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