%0 Journal Article
%T Protocol of measuring hot-spot correlation length for SNSPDs with near-unity detection efficiency
%A Polyakova, M.
%A Semenov, A. V.
%A Kovalyuk, V.
%A Ferrari, S.
%A Pernice, W. H. P.
%A Gol'tsman, G. N.
%J IEEE Trans. Appl. Supercond.
%D 2019
%V 29
%N 5
%@ 1051-8223
%F Polyakova_etal2019
%O exported from refbase (https://db.rplab.ru/refbase/show.php?record=1187), last updated on Sat, 01 May 2021 15:26:47 -0500
%X We present a simple quantum detector tomography protocol, which allows, without ambiguities, to measure the two-spot detection efficiency and extract the hot-spot interaction length of superconducting nanowire single photon detectors (SNSPDs) with unity intrinsic detection efficiency. We identify a significant parasitic contribution to the measured two-spot efficiency, related to an effect of the bias circuit, and find a way to rule out this contribution during data post-processing and directly in the experiment. From the data analysis for waveguide-integrated SNSPD, we find signatures of the saturation of the two-spot efficiency and hot-spot interaction length of order of 100 nm.
%K SSPD
%K waveguide-integrated SNSPD
%K hot-spot interaction length
%R 10.1109/TASC.2019.2906267
%U https://ieeexplore.ieee.org/document/8675504/
%U https://doi.org/10.1109/TASC.2019.2906267
%P 1-5