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arXiv · 1408.4907

Detection Mechanism in SNSPD: Numerical Results of a Conceptually Simple, Yet Powerful Detection Model

Andreas Engel·Julia Lonsky·Xiaofu Zhang·Andreas Schilling
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Abstract

In a recent publication we have proposed a numerical model that describes the detection process of optical photons in superconducting nanowire single-photon detectors (SNSPD). Here, we review this model and present a significant improvement that allows us to calculate more accurate current distributions for the inhomogeneous quasi-particle densities occurring after photon absorption. With this new algorithm we explore the detector response in standard NbN SNSPD for photons absorbed off-center and for 2-photon processes. We also discuss the outstanding performance of SNSPD based on WSi. Our numerical results indicate a different detection mechanism in WSi than in NbN or similar materials.

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Andreas Engel, Julia Lonsky, Xiaofu Zhang, Andreas Schilling. 2014-08-21. Detection Mechanism in SNSPD: Numerical Results of a Conceptually Simple, Yet Powerful Detection Model. https://doi.org/10.1109/tasc.2014.2371537

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