Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

IEEE Transactions on Applied Superconductivity

Photon Switching Statistics in Multistrip Superconducting Single-Photon Detectors

Alexander A. Korneev, Yu. P. Korneeva, Irina Florya, Alexander V. Semenov, Gregory N Gol'tsman

Published May 29, 2018• 2 citations
Publisher

Abstract

We study photon count statistics in superconducting single-photon detectors consisting of up to 70 narrow superconducting strips connected in parallel. Using interarrival time analysis, we demonstrate that our samples are operated in the “arm-trigger” regime and require up to seven subsequently absorbed photons to form a resistive state in the whole sample. We also performed numerical simulation of the light and dark count rates versus detector bias current, which are in good agreement with the experimental results.

DOI
10.1109/tasc.2018.2841933

Related papers

Photon counting statistics of superconducting single-photon detectors made of a three-layer WSi film

Irina Florya, Yu. P. Korneeva, M. Yu. Mikhaı̆lov +3 more

Superconducting nanowire single-photon detectors (SNSPD) are used in quantum optics when record-breaking time resolution, high speed, and exceptionally low levels of dark counts (false readings) are required. Their detection efficiency is limited, however, by the absorption coefficient of the ultrathin superconducting film for the detected radiation. One possible way of increasing the detector absorption without limiting its broadband response is to make a detector in the form of several vertically stacked layers and connect them in parallel. For the first time we have studied single-photon detection in a multilayer structure consisting of three superconducting layers of amorphous tungsten silicide (WSi) separated by thin layers of amorphous silicon. Two operating modes of the detector are illustrated: an avalanche regime and an arm-trigger regime. A shift in these modes occurs at currents of ∼0.5–0.6 times the critical current of the detector.

Low Temperature Physics•Mar 1, 2018•9 citations

Dark count rates and spectral sensitivity of superconducting single-photon detectors

Andreas Engel, Alexei Semenov, Heinz‐Wilhelm Hübers +2 more

Recent results for a superconducting single-photon counter are presented. The detection mechanism of the photon counter is based on the combined action of the hot-spot formation after photon absorption and the subsequent current-assisted formation of a normal domain in a thin and narrow superconducting strip. Dark count rates caused by fluctuations of the superconducting order parameter as a function of the applied current are discussed as well as the dependence of the spectral sensitivity on detector dimensions and material parameters.

•Jan 1, 2004•0 citations

Dark counts double switching rates in NbTiN Superconducting Nanowire Single Photon Detectors

Daniela Salvoni, Mikkel Ejrnaes, L. Parlato +5 more

Abstract In this work we present a study of the dark counts rate in a NbTiN Superconducting Nanowire Single Photon Detectors (SNSPD). We measure the distribution of the time intervals elapsed between two consecutive dark pulses at the fixed temperature of 4,2K. Due to the stochastic nature of the dark counts, the distribution is expected to have a Poisson shape but what we observe is a combination of two Poisson-like processes. A further analysis of the distributions dependence on the bias current highlights that the weight of the two process is not constant. In the scenario presented by Ejrnaes et al. [1], this result can confirm that, in this temperature regime, dark counts are generated mainly by multiple consecutive fluctuation events and the contribution to the dark counts rate coming from single fluctuations increases in the high bias current region.

Journal of Physics Conference Series•Jun 1, 2020•0 citations

Different Single-Photon Response of Wide and Narrow Superconducting MoxSi1−x Strips

Yu. P. Korneeva, N.N. Manova, I.N. Florya +4 more

The photon count rate (PCR) of superconducting single-photon detectors made of ${\mathrm{Mo}}_{x}{\mathrm{Si}}_{1\text{\ensuremath{-}}x}$ films shaped as a 2-$\ensuremath{\mu}\mathrm{m}$-wide strip and a 115-nm-wide meander strip line is studied experimentally as a function of the dc biasing current at different values of the perpendicular magnetic field. For the wide strip, a crossover current ${I}_{\mathrm{cross}}$ is observed, below which the PCR increases with an increasing magnetic field and above which it decreases. This behavior contrasts with the narrow ${\mathrm{Mo}}_{x}{\mathrm{Si}}_{1\text{\ensuremath{-}}x}$ meander, for which no crossover current is observed, thus suggesting different photon-detection mechanisms in the wide and narrow strips. Namely, we argue that in the wide strip the absorbed photon destroys superconductivity locally via the vortex-antivortex mechanism for the emergence of resistance, while in the narrow meander superconductivity is destroyed across the whole strip line, forming a hot belt. Accordingly, the different photon-detection mechanisms associated with vortices and the hot belt determine the qualitative difference in the dependence of the PCR on the magnetic field.

arXiv:1910.02491•Physical Review Applied•Feb 6, 2020•59 citations

Evaluation of NbTiN Superconducting Strip Photon Detectors With 0.1–30 µm Strip Widths

Tomohiro Haneishi, Masahiro Yabuno, Hiroki Kutsuma +2 more

We report the niobium titanium nitride (NbTiN) superconducting strip photon detectors (SSPDs) with strip widths ranging from 0.1 to 30 µm. The bias current dependences of the detection efficiencies at the 1550 nm wavelength and the dark count rates were systematically evaluated in the wide range of the strip widths. Single-photon detection was confirmed and a saturation trend in the bias current dependence of detection efficiency was also observed for all strip width SSPDs. In addition, we measured the physical properties of the NbTiN films and found the switching current of SSPDs gradually deviated lower from the estimated depairing current with increasing the strip width. Furthermore, the dark counts occurred at the lower bias current relative to the depairing current as the strip width increased. These results suggest that the bias current is unevenly distributed as the strip width increases and the concentrated bias current may induce the dark counts. Our results would provide valuable insights into a better understanding of SSPDs with a wide range of strip widths, the origin of dark counts, and the mechanism of photon detection in superconducting strip.

IEEE Transactions on Applied Superconductivity•Dec 25, 2024•4 citations

Vortex-assisted photon counts and their magnetic field dependence in single-photon superconducting detectors

Lev N. Bulaevskii, Matthias J. Graf, V. G. Kogan

We argue that photon counts in a superconducting nanowire single-photon detector (SNSPD) are caused by the transition from a current-biased metastable superconducting state to the normal state. Such a transition is triggered by vortices crossing the thin and narrow superconducting strip from one edge to another due to the Lorentz force. Detector counts in SNSPDs may be caused by three processes: (a) a single incident photon with sufficient energy to break enough Cooper pairs to create a normal-state belt across the entire width of the strip (direct photon count), (b) thermally induced single-vortex crossing in the absence of photons (dark count), which at high-bias currents releases the energy sufficient to trigger the transition to the normal state in a belt across the whole width of the strip, and (c) a single incident photon of insufficient energy to create a normal-state belt but initiating a subsequent single-vortex crossing, which provides the rest of the energy needed to create the normal-state belt (vortex-assisted single-photon count). We derive the current dependence of the rate of vortex-assisted photon counts. The resulting photon count rate has a plateau at high currents close to the critical current and drops as a power law with high exponent at lower currents. While the magnetic field perpendicular to the film plane does not affect the formation of hot spots by photons, it causes the rate of vortex crossings (with or without photons) to increase. We show that by applying a magnetic field one may characterize the energy barrier for vortex crossings and identify the origin of dark counts and vortex-assisted photon counts.

arXiv:1108.4004•Physical Review B•Jan 17, 2012•130 citations
We study photon count statistics in superconducting single-photon detectors consisting of up to 70 narrow superconducting strips connected in parallel. Using interarrival time analysis, we demonstrate that our samples are operated in the “arm-trigger” regime and require up to seven subsequently absorbed photons to form a resistive state in the whole sample. We also performed numerical simulation of the light and dark count rates versus detector bias current, which are in good agreement with the experimental results.
Superconducting nanowire single-photon detectors (SNSPD) are used in quantum optics when record-breaking time resolution, high speed, and exceptionally low levels of dark counts (false readings) are required. Their detection efficiency is limited, however, by the absorption coefficient of the ultrathin superconducting film for the detected radiation. One possible way of increasing the detector absorption without limiting its broadband response is to make a detector in the form of several vertically stacked layers and connect them in parallel. For the first time we have studied single-photon detection in a multilayer structure consisting of three superconducting layers of amorphous tungsten silicide (WSi) separated by thin layers of amorphous silicon. Two operating modes of the detector are illustrated: an avalanche regime and an arm-trigger regime. A shift in these modes occurs at currents of ∼0.5–0.6 times the critical current of the detector.
Recent results for a superconducting single-photon counter are presented. The detection mechanism of the photon counter is based on the combined action of the hot-spot formation after photon absorption and the subsequent current-assisted formation of a normal domain in a thin and narrow superconducting strip. Dark count rates caused by fluctuations of the superconducting order parameter as a function of the applied current are discussed as well as the dependence of the spectral sensitivity on detector dimensions and material parameters.
Abstract In this work we present a study of the dark counts rate in a NbTiN Superconducting Nanowire Single Photon Detectors (SNSPD). We measure the distribution of the time intervals elapsed between two consecutive dark pulses at the fixed temperature of 4,2K. Due to the stochastic nature of the dark counts, the distribution is expected to have a Poisson shape but what we observe is a combination of two Poisson-like processes. A further analysis of the distributions dependence on the bias current highlights that the weight of the two process is not constant. In the scenario presented by Ejrnaes et al. [1], this result can confirm that, in this temperature regime, dark counts are generated mainly by multiple consecutive fluctuation events and the contribution to the dark counts rate coming from single fluctuations increases in the high bias current region.
The photon count rate (PCR) of superconducting single-photon detectors made of ${\mathrm{Mo}}_{x}{\mathrm{Si}}_{1\text{\ensuremath{-}}x}$ films shaped as a 2-$\ensuremath{\mu}\mathrm{m}$-wide strip and a 115-nm-wide meander strip line is studied experimentally as a function of the dc biasing current at different values of the perpendicular magnetic field. For the wide strip, a crossover current Icross{I}_{\mathrm{cross}}Icross​ is observed, below which the PCR increases with an increasing magnetic field and above which it decreases. This behavior contrasts with the narrow ${\mathrm{Mo}}_{x}{\mathrm{Si}}_{1\text{\ensuremath{-}}x}$ meander, for which no crossover current is observed, thus suggesting different photon-detection mechanisms in the wide and narrow strips. Namely, we argue that in the wide strip the absorbed photon destroys superconductivity locally via the vortex-antivortex mechanism for the emergence of resistance, while in the narrow meander superconductivity is destroyed across the whole strip line, forming a hot belt. Accordingly, the different photon-detection mechanisms associated with vortices and the hot belt determine the qualitative difference in the dependence of the PCR on the magnetic field.
We report the niobium titanium nitride (NbTiN) superconducting strip photon detectors (SSPDs) with strip widths ranging from 0.1 to 30 µm. The bias current dependences of the detection efficiencies at the 1550 nm wavelength and the dark count rates were systematically evaluated in the wide range of the strip widths. Single-photon detection was confirmed and a saturation trend in the bias current dependence of detection efficiency was also observed for all strip width SSPDs. In addition, we measured the physical properties of the NbTiN films and found the switching current of SSPDs gradually deviated lower from the estimated depairing current with increasing the strip width. Furthermore, the dark counts occurred at the lower bias current relative to the depairing current as the strip width increased. These results suggest that the bias current is unevenly distributed as the strip width increases and the concentrated bias current may induce the dark counts. Our results would provide valuable insights into a better understanding of SSPDs with a wide range of strip widths, the origin of dark counts, and the mechanism of photon detection in superconducting strip.
We argue that photon counts in a superconducting nanowire single-photon detector (SNSPD) are caused by the transition from a current-biased metastable superconducting state to the normal state. Such a transition is triggered by vortices crossing the thin and narrow superconducting strip from one edge to another due to the Lorentz force. Detector counts in SNSPDs may be caused by three processes: (a) a single incident photon with sufficient energy to break enough Cooper pairs to create a normal-state belt across the entire width of the strip (direct photon count), (b) thermally induced single-vortex crossing in the absence of photons (dark count), which at high-bias currents releases the energy sufficient to trigger the transition to the normal state in a belt across the whole width of the strip, and (c) a single incident photon of insufficient energy to create a normal-state belt but initiating a subsequent single-vortex crossing, which provides the rest of the energy needed to create the normal-state belt (vortex-assisted single-photon count). We derive the current dependence of the rate of vortex-assisted photon counts. The resulting photon count rate has a plateau at high currents close to the critical current and drops as a power law with high exponent at lower currents. While the magnetic field perpendicular to the film plane does not affect the formation of hot spots by photons, it causes the rate of vortex crossings (with or without photons) to increase. We show that by applying a magnetic field one may characterize the energy barrier for vortex crossings and identify the origin of dark counts and vortex-assisted photon counts.