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

Applied Physics Letters

Vortex-crossing-induced timing jitter of superconducting nanowire single-photon detectors

Hao Wu, Chao Gu, Yuhao Cheng, Xiaolong Hu

Published Aug 7, 2017• 31 citations
Publisher

Abstract

We investigate the timing properties of single-photon-triggered vortex (or anti-vortex) crossing in a current-biased superconducting nanowire and find that the time delays caused in the vortex-crossing process vary with the transverse positions on the nanowire where the photons are absorbed. The position-dependent time delays indicate that the vortex-crossing process induces timing jitter of a superconducting nanowire single-photon detector (SNSPD). The magnitude of this timing jitter further depends on various parameters, including the polarization of the incident photon, the bias current, and the width of the nanowire. This vortex-crossing-induced timing jitter might represent the lower bound of the timing jitter of the SNSPD and fundamentally limit its time-resolving capability.

DOI
10.1063/1.4997930

Related papers

Vortex-Crossing-Induced Timing Jitter of Superconducting Nanowire Single-Photon Detectors

Hao Wu, Chao Gu, Yuhao Cheng +1 more

We show that single-photon-triggered vortex (or anti-vortex) crossing in a superconducting nanowire single-photon detector induces timing jitter, which fundamentally limits the time-resolving capability of the detector.

Conference on Lasers and Electro-Optics•Jan 1, 2017•0 citations

Probabilistic vortex crossing criterion for superconducting nanowire single-photon detectors

Saman Jahani, Li-Ping Yang, Adrián Buganza Tepole +3 more

Superconducting nanowire single-photon detectors have emerged as a promising technology for quantum metrology from the mid-infrared to ultraviolet frequencies. Despite recent experimental successes, a predictive model to describe the detection event in these detectors is needed to optimize the detection metrics. Here, we propose a probabilistic criterion for single-photon detection based on single-vortex (flux quanta) crossing the width of the nanowire. Our model makes a connection between the dark counts and photon counts near the detection threshold. The finite-difference calculations demonstrate that a change in the bias current distribution as a result of the photon absorption significantly increases the probability of single-vortex crossing even if the vortex potential barrier has not vanished completely. We estimate the instrument response function and show that the timing uncertainty of this vortex tunneling process corresponds to a fundamental limit in timing jitter of the click event. We demonstrate a trade-space between this intrinsic (quantum) timing jitter, quantum efficiency, and dark count rate in TaN, WSi, and NbN superconducting nanowires at different experimental conditions. Our detection model can also explain the experimental observation of exponential decrease in the quantum efficiency of SNSPDs at lower energies. This leads to a pulse-width dependency in the quantum efficiency, and it can be further used as an experimental test to compare across different detection models.

arXiv:1901.09291•Journal of Applied Physics•Apr 9, 2020•19 citations

Minimal Timing Jitter in Superconducting Nanowire Single-Photon Detectors

Denis Yu. Vodolazov

The results of this theoretical study are important for applications dealing with superconducting nanowire single-photon detectors (SNSPDs), which include quantum information processing. The author shows that the variation in delay time ${\ensuremath{\tau}}_{d}$ (timing jitter) of the voltage response after absorption of a single photon, connected to either position-dependent response or variation in the energy deposited to electrons, could be as small as 1 ps when the current in the superconducting strip approaches the depairing current. Reducing this jitter is a main topic of SNSPD research, and understanding the origins of these variations is necessary to that end.

arXiv:1807.07709•Physical Review Applied•Jan 9, 2019•32 citations

Inhomogeneity-induced timing jitter of superconducting nanowire single-photon detectors

Yuhao Cheng, Chao Gu, Xiaolong Hu

We show that the distributed electronic and geometric inhomogeneity of a superconducting nanowire induces timing jitter of the resulting single-photon detector and this timing jitter could be further exacerbated by localized constrictions. Due to the distributed inhomogeneity, photons absorbed at different locations of the nanowire generate hotspots that “sense” different local properties of the nanowire during the electro-thermal evolutions and thereby produce varying time delays. The localized constrictions limit the bias current, slow down the Joule-heating process, and consequently increase the average time delays and the inhomogeneity-induced timing jitter. We combine the Monte-Carlo method and the electro-thermal simulation to illustrate the inhomogeneity-induced timing jitter.

Applied Physics Letters•Aug 7, 2017•30 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

Superconducting nanowire single-photon detectors at the infrared spectrum range: detection efficiency and timing jitter

Xiaolong Hu, Nan Hu, Yun Meng +9 more

This paper reviews some recent research progress in superconducting nanowire single-photon detectors (SNSPDs) at the infrared spectrum range, with particular emphasis on detection efficiency and timing jitter. For detection efficiency, we present fractal SNSPDs with reduced polarization sensitivity; for timing jitter, we present two mechanisms of device timing jitter – vortex-crossing-induced timing jitter and spatial-inhomogeneity-induced timing jitter.

Terahertz, RF, Millimeter, and Submillimeter-Wave Technology and Applications•Mar 1, 2019•1 citation
We investigate the timing properties of single-photon-triggered vortex (or anti-vortex) crossing in a current-biased superconducting nanowire and find that the time delays caused in the vortex-crossing process vary with the transverse positions on the nanowire where the photons are absorbed. The position-dependent time delays indicate that the vortex-crossing process induces timing jitter of a superconducting nanowire single-photon detector (SNSPD). The magnitude of this timing jitter further depends on various parameters, including the polarization of the incident photon, the bias current, and the width of the nanowire. This vortex-crossing-induced timing jitter might represent the lower bound of the timing jitter of the SNSPD and fundamentally limit its time-resolving capability.
Superconducting nanowire single-photon detectors have emerged as a promising technology for quantum metrology from the mid-infrared to ultraviolet frequencies. Despite recent experimental successes, a predictive model to describe the detection event in these detectors is needed to optimize the detection metrics. Here, we propose a probabilistic criterion for single-photon detection based on single-vortex (flux quanta) crossing the width of the nanowire. Our model makes a connection between the dark counts and photon counts near the detection threshold. The finite-difference calculations demonstrate that a change in the bias current distribution as a result of the photon absorption significantly increases the probability of single-vortex crossing even if the vortex potential barrier has not vanished completely. We estimate the instrument response function and show that the timing uncertainty of this vortex tunneling process corresponds to a fundamental limit in timing jitter of the click event. We demonstrate a trade-space between this intrinsic (quantum) timing jitter, quantum efficiency, and dark count rate in TaN, WSi, and NbN superconducting nanowires at different experimental conditions. Our detection model can also explain the experimental observation of exponential decrease in the quantum efficiency of SNSPDs at lower energies. This leads to a pulse-width dependency in the quantum efficiency, and it can be further used as an experimental test to compare across different detection models.
The results of this theoretical study are important for applications dealing with superconducting nanowire single-photon detectors (SNSPDs), which include quantum information processing. The author shows that the variation in delay time ${\ensuremath{\tau}}_{d}$ (timing jitter) of the voltage response after absorption of a single photon, connected to either position-dependent response or variation in the energy deposited to electrons, could be as small as 1 ps when the current in the superconducting strip approaches the depairing current. Reducing this jitter is a main topic of SNSPD research, and understanding the origins of these variations is necessary to that end.
We show that the distributed electronic and geometric inhomogeneity of a superconducting nanowire induces timing jitter of the resulting single-photon detector and this timing jitter could be further exacerbated by localized constrictions. Due to the distributed inhomogeneity, photons absorbed at different locations of the nanowire generate hotspots that “sense” different local properties of the nanowire during the electro-thermal evolutions and thereby produce varying time delays. The localized constrictions limit the bias current, slow down the Joule-heating process, and consequently increase the average time delays and the inhomogeneity-induced timing jitter. We combine the Monte-Carlo method and the electro-thermal simulation to illustrate the inhomogeneity-induced timing jitter.
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.