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

Superconducting coincidence photon detector with short timing jitter

Shigehito Miki, Shigeyuki Miyajima, Masahiro Yabuno, Taro Yamashita, Takashi Yamamoto, N. Imoto, Rikizo Ikuta, Robert A. Kirkwood, Robert H. Hadfield, Hirotaka Terai

Published Jun 25, 2018• 24 citations
Publisher

Abstract

We demonstrate the operation of a coincidence photon detector with a short timing jitter consisting of two superconducting nanowire single photon detectors (SSPDs) and a single flux quantum (SFQ) circuit. By utilizing the timing discrimination capability of the SFQ coincidence circuit, the full width at half maximum timing jitter of the entire coincidence photon detector was evaluated as 32.3 ps, which is 36 ps less than that of the standard commercial time correlated single photon counting module, and the timing jitter of the SSPD was estimated as ∼15 ps. Owing to the short timing jitter characteristics, our coincidence photon detector could correctly capture the effect of pulse-width broadening by insertion of an optical bandpass filter. We have also demonstrated that our coincidence photon detection clearly shows Hong-Ou-Mandel interference with a weak coherent pulse. These results are a crucial step to realizing high timing resolution coincidence measurements, ushering in a technology for timing measurement based multi-photon quantum interference.

DOI
10.1063/1.5037254

Related papers

Timing Jitter Characterization of the SFQ Coincidence Circuit by Optically Time-Controlled Signals From SSPDs

Shigehito Miki, Shigeyuki Miyajima, Masahiro Yabuno +7 more

We report on the timing jitter characterization of the superconducting single flux quantum (SFQ) coincidence circuit, which is an essential component of the superconducting coincidence photon counter. Two superconducting nanowire single photon detectors (SSPDs), each of which is irradiated with optically time-controlled photons, are connected to the SFQ coincidence circuit, and the timing jitter of the SFQ circuit is evaluated by changing the relative time delay between two input ports for the SFQ comparator unit. We successfully observe the transition curve of the probability of obtaining the signal from the SFQ coincidence circuit by sweeping photon arrival time to each SSPD and confirm that this curve shifts temporally upon changing the bias current to the Josephson transmission line (JTL) in the SFQ circuit. A systematic investigation reveals that the relation between time delay and the bias current to JTL can be estimated. The full width half maximum timing jitter of the SFQ circuit is 1.1 ps, which is sufficiently low so that it does not influence the entire timing jitter of the coincidence photon counter.

IEEE Transactions on Applied Superconductivity•Apr 15, 2019•2 citations

Timing discriminator based on single-flux-quantum circuit toward high time-resolved photon detection

Shigeyuki Miyajima, Shigehito Miki, Masahiro Yabuno +2 more

Abstract We propose a new time discriminating method based on a single-flux quantum (SFQ) circuit to realize a high time-resolved single-photon detection scheme that uses a superconducting nanowire single-photon detector (SSPD). The timing discriminator consists of an SFQ comparator and an interface circuit for converting the output signals of an SSPD into SFQ pulses. Prior to connecting with the SSPD, we evaluated the timing jitters of the SFQ timing discriminator itself by applying external electrical pulses. The timing jitters of the SFQ timing discriminator were found to be dominated by the timing jitters in the interface circuit. However, it was estimated to be below 10 ps even with an input pulse amplitude of 20 μ A, which is close to the typical output amplitude of the SSPD.

Superconductor Science and Technology•Oct 10, 2017•13 citations

Low-jitter single flux quantum signal readout from superconducting single photon detector

Hirotaka Terai, Taro Yamashita, Shigehito Miki +2 more

We developed a single-flux-quantum (SFQ) readout technology for superconducting single-photon detectors (SSPDs) to achieve low-jitter signal readout. By optimizing circuit parameters of the SFQ readout circuit, the input current sensitivity was improved below 10 μA, which is smaller than a typical critical current of SSPD. The experiment using a pulse-pattern generator as an input pulse source revealed that the measured jitter of the SFQ readout circuit is well below the system jitter of our measurement setup for the input current level above 15 μA. The measured jitter of the SSPD connected to the SFQ readout circuit was 37 ps full width at half maximum (FWHM) for an SSPD bias current of around 18 μA, which is a significant improvement on 67 ps FWHM jitter observed in conventional readout without an SFQ readout circuit.

Optics Express•Aug 17, 2012•41 citations

Improving the timing jitter of a superconducting nanowire single-photon detection system

Junjie Wu, Lixing You, Sijing Chen +5 more

Low timing jitter is a unique merit of superconducting nanowire single-photon detectors (SNSPDs) for time-correlated applications. Quantitative analysis was performed for the SNSPD system. Aided by an oscilloscope with an optimal signal amplitude, we were able to measure a full width at half-maximum system timing jitter as low as 14.2 ps for a high-switching-current SNSPD using a room-temperature low-noise amplifier. When using a time-correlated single-photon counting module, the system timing jitter was 17.3 ps. The detector's intrinsic timing jitter was estimated at ∼12.0 ps.

Applied Optics•Mar 6, 2017•96 citations

Design of integrated SSPD-SFQ two-photon coincidence correlator

I. Komissarov, Amir Jafari Salim, Oleg A. Mukhanov +3 more

We present a single-flux-quantum (SFQ) based digital correlator to trace independent signals from two superconducting single-photon detectors (SSPDs) triggering its inputs. In our design two SSPDs are magnetically coupled to inputs of a readout system where direct current (DC)-to-SFQ converters are used to convert transient SSPD output pulses, triggered by detection of single-photon events, to SFQ pulses. The coincidence verification of SFQ pulses, generated by the two DC-to-SFQ converters, is performed with a modified SFQ coincidence buffer. The coincidence buffer is designed to generate an SFQ output pulse only when its both inputs are triggered simultaneously, or within a preset margin time. The output of the coincidence buffer is connected via, this time, an SFQ-to-DC converter, to a pulse counter operated at room temperature. We performed extensive simulations of both the SSPD equivalent circuit and correlator redout elements for the proposed coincidence scheme, using a WRSpice and PSCAN2 simulation platforms that are specifically designated to model Josephson junctions and widely used to simulate operation of the SFQ circuitry. In particular, we investigated our coincidence correlator scheme for measurements of the second-order correlation function, used to demonstrate the antibunching effect in the single-photon detection of non-classical light.

Quantum Optics and Photon Counting•Jun 6, 2023•2 citations

A superconducting nanowire single-photon detector system for single-photon source characterization

Catherine R. M. Fitzpatrick, Chandra M. Natarajan, Ryan E. Warburton +8 more

Single-photon sources and detectors are key enabling technologies for photonics in quantum information science and technology (QIST). QIST applications place high-level demands on the performance of sources and detectors; it is therefore essential that their properties can be characterized accurately. Superconducting nanowire single-photon detectors (SNSPDs) have spectral sensitivity from visible to beyond 2 μm in wavelength, picosecond timing resolution (Jitter <100 ps FWHM) and the capacity to operate ungated with low dark counts (<1 kHz). This facilitates data acquisition at high rates with an excellent signal-to-noise ratio. We report on the construction and characterization of a two-channel SNSPD system. The detectors are mounted in a closed-cycle refrigerator, which eliminates reliance on liquid cryogens. Our specification was to deliver a system with 1% efficiency in both channels at a wavelength of 1310 nm with 1 kHz dark count rate. A full width at half maximum timing jitter of less than 90 ps is achieved in both channels. The system will be used to detect individual photons generated by quantum-optical sources at telecom wavelengths. Examples include single-photon sources based on quantum dots (emitting at 1310 nm). The SNSPD system's spectral sensitivity and timing resolution make it suited to characterization of such sources, and to wider QIST applications.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Apr 20, 2010•0 citations
We demonstrate the operation of a coincidence photon detector with a short timing jitter consisting of two superconducting nanowire single photon detectors (SSPDs) and a single flux quantum (SFQ) circuit. By utilizing the timing discrimination capability of the SFQ coincidence circuit, the full width at half maximum timing jitter of the entire coincidence photon detector was evaluated as 32.3 ps, which is 36 ps less than that of the standard commercial time correlated single photon counting module, and the timing jitter of the SSPD was estimated as ∼15 ps. Owing to the short timing jitter characteristics, our coincidence photon detector could correctly capture the effect of pulse-width broadening by insertion of an optical bandpass filter. We have also demonstrated that our coincidence photon detection clearly shows Hong-Ou-Mandel interference with a weak coherent pulse. These results are a crucial step to realizing high timing resolution coincidence measurements, ushering in a technology for timing measurement based multi-photon quantum interference.
We report on the timing jitter characterization of the superconducting single flux quantum (SFQ) coincidence circuit, which is an essential component of the superconducting coincidence photon counter. Two superconducting nanowire single photon detectors (SSPDs), each of which is irradiated with optically time-controlled photons, are connected to the SFQ coincidence circuit, and the timing jitter of the SFQ circuit is evaluated by changing the relative time delay between two input ports for the SFQ comparator unit. We successfully observe the transition curve of the probability of obtaining the signal from the SFQ coincidence circuit by sweeping photon arrival time to each SSPD and confirm that this curve shifts temporally upon changing the bias current to the Josephson transmission line (JTL) in the SFQ circuit. A systematic investigation reveals that the relation between time delay and the bias current to JTL can be estimated. The full width half maximum timing jitter of the SFQ circuit is 1.1 ps, which is sufficiently low so that it does not influence the entire timing jitter of the coincidence photon counter.
Abstract We propose a new time discriminating method based on a single-flux quantum (SFQ) circuit to realize a high time-resolved single-photon detection scheme that uses a superconducting nanowire single-photon detector (SSPD). The timing discriminator consists of an SFQ comparator and an interface circuit for converting the output signals of an SSPD into SFQ pulses. Prior to connecting with the SSPD, we evaluated the timing jitters of the SFQ timing discriminator itself by applying external electrical pulses. The timing jitters of the SFQ timing discriminator were found to be dominated by the timing jitters in the interface circuit. However, it was estimated to be below 10 ps even with an input pulse amplitude of 20 μ A, which is close to the typical output amplitude of the SSPD.
We developed a single-flux-quantum (SFQ) readout technology for superconducting single-photon detectors (SSPDs) to achieve low-jitter signal readout. By optimizing circuit parameters of the SFQ readout circuit, the input current sensitivity was improved below 10 μA, which is smaller than a typical critical current of SSPD. The experiment using a pulse-pattern generator as an input pulse source revealed that the measured jitter of the SFQ readout circuit is well below the system jitter of our measurement setup for the input current level above 15 μA. The measured jitter of the SSPD connected to the SFQ readout circuit was 37 ps full width at half maximum (FWHM) for an SSPD bias current of around 18 μA, which is a significant improvement on 67 ps FWHM jitter observed in conventional readout without an SFQ readout circuit.
Low timing jitter is a unique merit of superconducting nanowire single-photon detectors (SNSPDs) for time-correlated applications. Quantitative analysis was performed for the SNSPD system. Aided by an oscilloscope with an optimal signal amplitude, we were able to measure a full width at half-maximum system timing jitter as low as 14.2 ps for a high-switching-current SNSPD using a room-temperature low-noise amplifier. When using a time-correlated single-photon counting module, the system timing jitter was 17.3 ps. The detector's intrinsic timing jitter was estimated at ∼12.0 ps.
We present a single-flux-quantum (SFQ) based digital correlator to trace independent signals from two superconducting single-photon detectors (SSPDs) triggering its inputs. In our design two SSPDs are magnetically coupled to inputs of a readout system where direct current (DC)-to-SFQ converters are used to convert transient SSPD output pulses, triggered by detection of single-photon events, to SFQ pulses. The coincidence verification of SFQ pulses, generated by the two DC-to-SFQ converters, is performed with a modified SFQ coincidence buffer. The coincidence buffer is designed to generate an SFQ output pulse only when its both inputs are triggered simultaneously, or within a preset margin time. The output of the coincidence buffer is connected via, this time, an SFQ-to-DC converter, to a pulse counter operated at room temperature. We performed extensive simulations of both the SSPD equivalent circuit and correlator redout elements for the proposed coincidence scheme, using a WRSpice and PSCAN2 simulation platforms that are specifically designated to model Josephson junctions and widely used to simulate operation of the SFQ circuitry. In particular, we investigated our coincidence correlator scheme for measurements of the second-order correlation function, used to demonstrate the antibunching effect in the single-photon detection of non-classical light.
Single-photon sources and detectors are key enabling technologies for photonics in quantum information science and technology (QIST). QIST applications place high-level demands on the performance of sources and detectors; it is therefore essential that their properties can be characterized accurately. Superconducting nanowire single-photon detectors (SNSPDs) have spectral sensitivity from visible to beyond 2 μm in wavelength, picosecond timing resolution (Jitter <100 ps FWHM) and the capacity to operate ungated with low dark counts (<1 kHz). This facilitates data acquisition at high rates with an excellent signal-to-noise ratio. We report on the construction and characterization of a two-channel SNSPD system. The detectors are mounted in a closed-cycle refrigerator, which eliminates reliance on liquid cryogens. Our specification was to deliver a system with 1% efficiency in both channels at a wavelength of 1310 nm with 1 kHz dark count rate. A full width at half maximum timing jitter of less than 90 ps is achieved in both channels. The system will be used to detect individual photons generated by quantum-optical sources at telecom wavelengths. Examples include single-photon sources based on quantum dots (emitting at 1310 nm). The SNSPD system's spectral sensitivity and timing resolution make it suited to characterization of such sources, and to wider QIST applications.