Dependence of Photon Detection Efficiency on Normal-State Sheet Resistance in Marginally Superconducting Films of NbN

We present an extensive set of data on nanowire-type superconducting single-photon detectors based on niobium-nitride (NbN) to establish the empirical correlation between performance and the normal-state resistance per square. We focus, in particular, on the bias current, compared to the expected de...

Full description

Saved in:
Bibliographic Details
Published in:IEEE transactions on applied superconductivity 2021-08, Vol.31 (5), p.1-5
Main Authors: Zolotov, Philipp I., Semenov, Alexander V., Divochiy, Alexander V., Goltsman, Gregory N., Romanov, Nikita R., Klapwijk, Teunis M.
Format: Article
Language:English
Subjects:
Nanowires
Niobium compounds
Niobium nitride
Phase coherence
Photons
Superconducting films
Superconducting photodetectors
Superconductivity
Superconductors
Thermal runaway
Thin films
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We present an extensive set of data on nanowire-type superconducting single-photon detectors based on niobium-nitride (NbN) to establish the empirical correlation between performance and the normal-state resistance per square. We focus, in particular, on the bias current, compared to the expected depairing current, needed to achieve a near-unity detection efficiency for photon detection. The data are discussed within the context of a model in which the photon energy triggers the movement of vortices i.e. superconducting dissipation, followed by thermal runaway. Since the model is based on the non-equilibrium theory for conventional superconductors deviations may occur, because the efficient regime is found when NbN acts as a marginal superconductor in which long-range phase coherence is frustrated.
ISSN:1051-8223
1558-2515
DOI:10.1109/TASC.2021.3061923