%0 Journal Article %T Dependence of photon detection efficiency on normal-state sheet resistance in marginally superconducting films of NbN %A Zolotov, P. I. %A Semenov, A. V. %A Divochiy, A. V. %A Goltsman, G. N. %A Romanov, N. R. %A Klapwijk, T. M. %J IEEE Trans. Appl. Supercond. %D 2021 %V 31 %N 5 %@ 1051-8223 %F Zolotov_etal2021 %O exported from refbase (https://db.rplab.ru/refbase/show.php?record=1222), last updated on Mon, 03 May 2021 22:14:28 -0500 %X 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. %K NbN SSPD %K SNSPD %R 10.1109/TASC.2021.3061923 %U https://ieeexplore.ieee.org/document/9362289/ %U https://doi.org/10.1109/TASC.2021.3061923 %P 1-5