TY  - JOUR
AU  - Polyakova, M.
AU  - Semenov, A. V.
AU  - Kovalyuk, V.
AU  - Ferrari, S.
AU  - Pernice, W. H. P.
AU  - Gol'tsman, G. N.
PY  - 2019
DA  - 2019//
TI  - Protocol of measuring hot-spot correlation length for SNSPDs with near-unity detection efficiency
T2  - IEEE Trans. Appl. Supercond.
JO  - IEEE Trans. Appl. Supercond.
SP  - 1
EP  - 5
VL  - 29
IS  - 5
KW  - SSPD
KW  - waveguide-integrated SNSPD
KW  - hot-spot interaction length
AB  - 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.
SN  - 1051-8223
UR  - https://ieeexplore.ieee.org/document/8675504/
UR  - https://doi.org/10.1109/TASC.2019.2906267
DO  - 10.1109/TASC.2019.2906267
N1  - exported from refbase (https://db.rplab.ru/refbase/show.php?record=1187), last updated on Sat, 01 May 2021 15:26:47 -0500
ID  - Polyakova_etal2019
ER  -