TY  - JOUR
AU  - Ferrari, S.
AU  - Kovalyuk, V.
AU  - Hartmann, W.
AU  - Vetter, A.
AU  - Kahl, O.
AU  - Lee, C.
AU  - Korneev, A.
AU  - Rockstuhl, C.
AU  - Gol'tsman, G.
AU  - Pernice, W.
PY  - 2017
DA  - 2017//
TI  - Hot-spot relaxation time current dependence in niobium nitride waveguide-integrated superconducting nanowire single-photon detectors
T2  - Opt. Express
JO  - Opt. Express
SP  - 8739
EP  - 8750
VL  - 25
IS  - 8
KW  - SSPD
KW  - SNSPD
KW  - photon counting
KW  - Infrared
KW  - Quantum detectors
KW  - Integrated optics
KW  - Multiphoton processes
KW  - Photon statistics
AB  - We investigate how the bias current affects the hot-spot relaxation dynamics in niobium nitride. We use for this purpose a near-infrared pump-probe technique on a waveguide-integrated superconducting nanowire single-photon detector driven in the two-photon regime. We observe a strong increase in the picosecond relaxation time for higher bias currents. A minimum relaxation time of (22 +/- 1)ps is obtained when applying a bias current of 50% of the switching current at 1.7 K bath temperature. We also propose a practical approach to accurately estimate the photon detection regimes based on the reconstruction of the measured detector tomography at different bias currents and for different illumination conditions.
N1  - exported from refbase (https://db.rplab.ru/refbase/show.php?record=1118), last updated on Sat, 01 May 2021 23:21:39 -0500
ID  - Ferrari_etal2017
ER  -