TY  - JOUR
AU  - Korneeva, Y. P.
AU  - Manova, N. N.
AU  - Dryazgov, M. A.
AU  - Simonov, N. O.
AU  - Zolotov, P. I.
AU  - Korneev, A. A.
PY  - 2021
DA  - 2021//
TI  - Influence of sheet resistance and strip width on the detection efficiency saturation in micron-wide superconducting strips and large-area meanders
T2  - Supercond. Sci. Technol.
JO  - Supercond. Sci. Technol.
SP  - 084001
VL  - 34
IS  - 8
KW  - NbN SSPD
KW  - SMSPD
AB  - We report our study of detection efficiency (DE) saturation in wavelength range 400 - 1550 nm for the NbN Superconducting Microstrip Single-Photon Detectors (SMSPD) featuring the strip width up to 3 μm. We observe an expected decrease of the $DE$ saturation plateau with the increase of photon wavelength and decrease of film sheet resistance. At 1.7 K temperature DE saturation can be clearly observed at 1550 nm wavelength in strip with the width up to 2 μm when sheet resistance of the film is above 630Ω/sq. In such strips the length of the saturation plateau almost does not depend on the strip width. We used these films to make meander-shaped detectors with the light sensitive area from 20×20μm2 to a circle 50 μm in diameter. In the latter case, the detector with the strip width of 0.49 μm demonstrates saturation of DE up to 1064 nm wavelength. Although DE at 1310 and 1550 nm is not saturated, it is as high as 60%. The response time is limited by the kinetic inductance and equals to 20 ns(by 1/e decay), timing jitter is 44 ps. When coupled to multi-mode fibre large-area meanders demonstrate significantly higher dark count rate which we attribute to thermal background photons, thus advanced filtering technique would be required for practical applications.
SN  - 0953-2048
UR  - https://iopscience.iop.org/article/10.1088/1361-6668/ac0950
UR  - https://doi.org/10.1088/1361-6668/ac0950
DO  - 10.1088/1361-6668/ac0950
N1  - exported from refbase (https://db.rplab.ru/refbase/show.php?record=1793), last updated on Sat, 03 Jul 2021 17:26:25 -0500
ID  - Korneeva_etal2021
ER  -