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

Optics Express

Two-micron-wavelength single-photon detection using the high-critical-current-bank structure superconducting wide strip photon detector

Masahiro Yabuno, Fumihiro China, Hirotaka Terai, Shigehito Miki

Published May 22, 2025• 4 citations
Publisher

Abstract

Superconducting strip photon detector is a promising technology for achieving high detection efficiency around the 2000 nm wavelength region where exciting applications are expected in fields ranging from quantum science to atmospheric physics. However, improving the single-photon sensitivity usually requires narrower nanostrips, which necessitates advanced fabrication technologies. We demonstrate high-efficiency single-photon detection at 2000 nm using a 20-μm-wide superconducting strip, which is approximately 200 times wider than conventional nanostrips. By combining a high critical current bank (HCCB) structure that improves the wide strip's single-photon sensitivity with an optical cavity structure designed for the 2000 nm wavelength band, we realize system detection efficiency of 70% with near-unity internal detection efficiency. These results provide a high-productivity approach for high-performance single-photon detector development for the 2000 nm band.

DOI
10.1364/oe.565820

Related papers

Superconducting wide strip photon detector with high critical current bank structure

Masahiro Yabuno, Fumihiro China, Hirotaka Terai +1 more

The single-photon detector is an essential technology in photonic quantum information science and technology. Large-scale photonic quantum computers and quantum networks inevitably require numerous high-performance single-photon detectors. Superconducting nanostrip single-photon detectors (SNSPDs) using around 100-nm-wide nanostrips are promising technologies with high detection efficiency, low dark count, and low jitter, but there has been room for evolution in terms of polarization dependence and productivity. Using wide strips with widths of tens of micrometers provides polarization-independent high detection efficiency and high-yield fabrication using high-throughput photolithography with submicron resolution. However, detecting photons with such wide strips has been challenging due to rapidly increasing intrinsic dark counts caused by the uneven distribution of the superconducting current in the strip. Here, we present a novel superconducting wide strip photon detector (SWSPD) with a high critical current bank (HCCB) structure. This new strip structure suppresses the intrinsic dark counts and provides highly efficient photon detection in the wide strips. We have simultaneously achieved a polarization-independent detection efficiency of over 78% for 1550-nm wavelength photons, a low dark count rate (DCR) of ∼80 cps, and a low jitter of 29.8 ps using a 20-µm-wide SWSPD with the HCCB structure. This result paves the way for a new class of photon detectors using ultra-wide superconducting strips. These photon detectors with excellent productivity and polarization-independent high detection performances would boost the advance of large-scale photonic quantum technologies.

arXiv:2305.06583•Optica Quantum•Sep 29, 2023•20 citations

Superconducting NbN microstrip single-photon detectors

Alexander A. Korneev

Superconducting Single-Photon Detectors (SSPD) invented two decades ago have evolved to a mature technology and have become devices of choice in the advanced applications of quantum optics, such as quantum cryptography and optical quantum computing. In these applications SSPDs are coupled to single-mode fibers and feature almost unity detection efficiency, negligible dark counts, picosecond timing jitter and MHz photon count rate. Meanwhile, there are great many applications requiring coupling to multi-mode fibers or free space. `Classical’ SSPDs with 100-nm-wide superconducting strip and covering area of about 100 µm2 are not suitable for further scaling due to degradation of performance and low fabrication yield. Recently we have demonstrated single-photon counting in micron-wide superconducting bridges and strips. Here we present our approach to the realization of practical photon-counting detectors of large enough area to be efficiently coupled to multi-mode fibers or free space. The detector is either a meander or a spiral of 1-µm-wide strip covering an area of 50x50 µm2. Being operated at 1.7K temperature it demonstrates the saturated detection efficiency (i.e. limited by the absorption in the detector) up to 1550 nm wavelength, about 10 ns dead time and timing jitter in range 50-100 ps.

Quantum Optics and Photon Counting•Apr 19, 2021•0 citations

Spectral sensitivity of narrow strip NbN superconducting single-photon detector

Alexander A. Korneev, Yu. P. Korneeva, Irina Florya +2 more

Superconducting single-photon detector (SSPD) is patterned from 4-nm-thick NbN film deposited on sapphire substrate as a 100-nm-wide strip. Due to its high detection efficiency, low dark counts, and picosecond timing jitter SSPD has become a competitor to the InGaAs avalanche photodiodes at 1550 nm and longer wavelengths. Although the SSPD is operated at liquid helium temperature its efficient single-mode fibre coupling enabled its usage in many applications ranging from single-photon sources research to quantum cryptography. In our strive to increase the detection efficiency at 1550 nm and longer wavelengths we developed and fabricated SSPD with the strip almost twice narrower compared to the standard 100 nm. To increase the voltage response of the device we utilized cascade switching mechanism: we connected 50-nm-wide and 10-μm-long strips in parallel covering the area of 10 μmx10 μm. Absorption of a photon breaks the superconductivity in a strip leading to the bias current redistribution between other strips followed their cascade switching. As the total current of all the strips about is 1 mA by the order of magnitude the response voltage of such an SSPD is several times higher compared to the traditional meander-shaped SSPDs. In middle infrared (about 3 μm wavelength) these devices have the detection efficiency several times higher compared to the traditional SSPDs.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Apr 29, 2011•3 citations

Efficient Single Photon Detection from 500 nm to 5 μm Wavelength

Francesco Marsili, Francesco Bellei, Faraz Najafi +4 more

We report on superconducting nanowire single photon detectors (SNSPDs) based on 30 nm wide nanowires with detection efficiency η ∼ 2.6-5.5% in the wavelength range λ = 0.5-5 μm. We compared the sensitivity of 30 nm wide SNSPDs with the sensitivity of SNSPDs based on wider (85 and 50 nm wide) nanowires for λ = 0.5-5 μm. The detection efficiency of the detectors based on the wider nanowires became negligible at shorter wavelengths than the 30 nm wide SNSPDs. Our 30 nm wide SNSPDs showed 2 orders of magnitude higher detection efficiency (η ∼ 2%) up to longer wavelength (λ = 5 μm) than previously reported. On the basis of our simulations, we expect that by changing the optical coupling scheme and by integrating the detectors in an optical cavity, the detection efficiency of our detectors could be increased by a factor of ∼6.

Nano Letters•Aug 13, 2012•197 citations

Superconducting nanowire single photon detector with efficiency over 90% at 2 μm wavelength

Zhen Wan, Jia Huang, Guangzhao Xu +6 more

Abstract We here report a high system detection efficiency (SDE) superconducting single-photon detector (SSPD) at 2 μm wavelength. The device integrates a SiO 2 /Ta 2 O 5 distributed Bragg reflector (DBR) and a sandwich-structured double-layer NbN nanowire to enhance the optical absorption efficiency. A cold development technique is implemented to optimize the superconducting nanowires with sub-40-nm linewidths, thus enhancing the intrinsic detection efficiency (IDE). The fabricated SSPD shows an SDE exceeding 90% at 2 μm wavelength. Moreover, the detector allows an operational working temperature of 2.2 K provided by a compact GM cryo-cooler. This detector delivers excellent performance at the 2 μm wavelength, and its optimized structural design implies promising potential for extending detection toward longer infrared bands. It thus holds value for advancing high-sensitivity quantum technologies, mid-infrared optical communications, and dark matter detection research.

Chinese Physics B•Nov 5, 2025•0 citations

Superconducting microstrip single-photon detector with system detection efficiency over 90% at 1550 nm

Guangzhao Xu, Wei-Jun Zhang, Li-Xing You +9 more

Generally, a superconducting nanowire single-photon detector (SNSPD) is composed of wires with a typical width of ∼ 100 nm . Recent studies have found that superconducting strips with a micrometer-scale width can also detect single photons. Compared with the SNSPD covering the same area, the superconducting microstrip single-photon detector (SMSPD) has smaller kinetic inductance, higher working current, and lower requirements in fabrication accuracy, providing potential applications in the development of ultralarge active area detectors. However, the study of SMSPD is still in its infancy, and the realization of its high-performance and practical use remains an open question. This study demonstrates a NbN SMSPD with a nearly saturated system detection efficiency (SDE) of ∼ 92.2 % at a dark count rate of ∼ 200 cps , a polarization sensitivity of ∼ 1.03 , and a minimum timing jitter of ∼ 48 ps at the telecom wavelength of 1550 nm when coupled with a single-mode fiber and operated at 0.84 K. Furthermore, the detector’s SDE is over 70% when operated at a 2.1 K closed-cycle cryocooler.

arXiv:2101.05407•Photonics Research•Mar 23, 2021•68 citations
Superconducting strip photon detector is a promising technology for achieving high detection efficiency around the 2000 nm wavelength region where exciting applications are expected in fields ranging from quantum science to atmospheric physics. However, improving the single-photon sensitivity usually requires narrower nanostrips, which necessitates advanced fabrication technologies. We demonstrate high-efficiency single-photon detection at 2000 nm using a 20-μm-wide superconducting strip, which is approximately 200 times wider than conventional nanostrips. By combining a high critical current bank (HCCB) structure that improves the wide strip's single-photon sensitivity with an optical cavity structure designed for the 2000 nm wavelength band, we realize system detection efficiency of 70% with near-unity internal detection efficiency. These results provide a high-productivity approach for high-performance single-photon detector development for the 2000 nm band.
The single-photon detector is an essential technology in photonic quantum information science and technology. Large-scale photonic quantum computers and quantum networks inevitably require numerous high-performance single-photon detectors. Superconducting nanostrip single-photon detectors (SNSPDs) using around 100-nm-wide nanostrips are promising technologies with high detection efficiency, low dark count, and low jitter, but there has been room for evolution in terms of polarization dependence and productivity. Using wide strips with widths of tens of micrometers provides polarization-independent high detection efficiency and high-yield fabrication using high-throughput photolithography with submicron resolution. However, detecting photons with such wide strips has been challenging due to rapidly increasing intrinsic dark counts caused by the uneven distribution of the superconducting current in the strip. Here, we present a novel superconducting wide strip photon detector (SWSPD) with a high critical current bank (HCCB) structure. This new strip structure suppresses the intrinsic dark counts and provides highly efficient photon detection in the wide strips. We have simultaneously achieved a polarization-independent detection efficiency of over 78% for 1550-nm wavelength photons, a low dark count rate (DCR) of ∼80 cps, and a low jitter of 29.8 ps using a 20-µm-wide SWSPD with the HCCB structure. This result paves the way for a new class of photon detectors using ultra-wide superconducting strips. These photon detectors with excellent productivity and polarization-independent high detection performances would boost the advance of large-scale photonic quantum technologies.
Superconducting Single-Photon Detectors (SSPD) invented two decades ago have evolved to a mature technology and have become devices of choice in the advanced applications of quantum optics, such as quantum cryptography and optical quantum computing. In these applications SSPDs are coupled to single-mode fibers and feature almost unity detection efficiency, negligible dark counts, picosecond timing jitter and MHz photon count rate. Meanwhile, there are great many applications requiring coupling to multi-mode fibers or free space. `Classical’ SSPDs with 100-nm-wide superconducting strip and covering area of about 100 µm2 are not suitable for further scaling due to degradation of performance and low fabrication yield. Recently we have demonstrated single-photon counting in micron-wide superconducting bridges and strips. Here we present our approach to the realization of practical photon-counting detectors of large enough area to be efficiently coupled to multi-mode fibers or free space. The detector is either a meander or a spiral of 1-µm-wide strip covering an area of 50x50 µm2. Being operated at 1.7K temperature it demonstrates the saturated detection efficiency (i.e. limited by the absorption in the detector) up to 1550 nm wavelength, about 10 ns dead time and timing jitter in range 50-100 ps.
Superconducting single-photon detector (SSPD) is patterned from 4-nm-thick NbN film deposited on sapphire substrate as a 100-nm-wide strip. Due to its high detection efficiency, low dark counts, and picosecond timing jitter SSPD has become a competitor to the InGaAs avalanche photodiodes at 1550 nm and longer wavelengths. Although the SSPD is operated at liquid helium temperature its efficient single-mode fibre coupling enabled its usage in many applications ranging from single-photon sources research to quantum cryptography. In our strive to increase the detection efficiency at 1550 nm and longer wavelengths we developed and fabricated SSPD with the strip almost twice narrower compared to the standard 100 nm. To increase the voltage response of the device we utilized cascade switching mechanism: we connected 50-nm-wide and 10-μm-long strips in parallel covering the area of 10 μmx10 μm. Absorption of a photon breaks the superconductivity in a strip leading to the bias current redistribution between other strips followed their cascade switching. As the total current of all the strips about is 1 mA by the order of magnitude the response voltage of such an SSPD is several times higher compared to the traditional meander-shaped SSPDs. In middle infrared (about 3 μm wavelength) these devices have the detection efficiency several times higher compared to the traditional SSPDs.
We report on superconducting nanowire single photon detectors (SNSPDs) based on 30 nm wide nanowires with detection efficiency η ∼ 2.6-5.5% in the wavelength range λ = 0.5-5 μm. We compared the sensitivity of 30 nm wide SNSPDs with the sensitivity of SNSPDs based on wider (85 and 50 nm wide) nanowires for λ = 0.5-5 μm. The detection efficiency of the detectors based on the wider nanowires became negligible at shorter wavelengths than the 30 nm wide SNSPDs. Our 30 nm wide SNSPDs showed 2 orders of magnitude higher detection efficiency (η ∼ 2%) up to longer wavelength (λ = 5 μm) than previously reported. On the basis of our simulations, we expect that by changing the optical coupling scheme and by integrating the detectors in an optical cavity, the detection efficiency of our detectors could be increased by a factor of ∼6.
Abstract We here report a high system detection efficiency (SDE) superconducting single-photon detector (SSPD) at 2 μm wavelength. The device integrates a SiO 2 /Ta 2 O 5 distributed Bragg reflector (DBR) and a sandwich-structured double-layer NbN nanowire to enhance the optical absorption efficiency. A cold development technique is implemented to optimize the superconducting nanowires with sub-40-nm linewidths, thus enhancing the intrinsic detection efficiency (IDE). The fabricated SSPD shows an SDE exceeding 90% at 2 μm wavelength. Moreover, the detector allows an operational working temperature of 2.2 K provided by a compact GM cryo-cooler. This detector delivers excellent performance at the 2 μm wavelength, and its optimized structural design implies promising potential for extending detection toward longer infrared bands. It thus holds value for advancing high-sensitivity quantum technologies, mid-infrared optical communications, and dark matter detection research.
Generally, a superconducting nanowire single-photon detector (SNSPD) is composed of wires with a typical width of ∼ 100 nm . Recent studies have found that superconducting strips with a micrometer-scale width can also detect single photons. Compared with the SNSPD covering the same area, the superconducting microstrip single-photon detector (SMSPD) has smaller kinetic inductance, higher working current, and lower requirements in fabrication accuracy, providing potential applications in the development of ultralarge active area detectors. However, the study of SMSPD is still in its infancy, and the realization of its high-performance and practical use remains an open question. This study demonstrates a NbN SMSPD with a nearly saturated system detection efficiency (SDE) of ∼ 92.2 % at a dark count rate of ∼ 200 cps , a polarization sensitivity of ∼ 1.03 , and a minimum timing jitter of ∼ 48 ps at the telecom wavelength of 1550 nm when coupled with a single-mode fiber and operated at 0.84 K. Furthermore, the detector’s SDE is over 70% when operated at a 2.1 K closed-cycle cryocooler.