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Author Korneev, A.; Korneeva, Y.; Florya, I.; Voronov, B.; Goltsman, G.
Title Spectral sensitivity of narrow strip NbN superconducting single-photon detector Type Conference Article
Year 2011 Publication Proc. SPIE Abbreviated Journal Proc. SPIE
Volume 8072 Issue Pages 80720G (1 to 9)
Keywords NbN SSPD, SNSPD
Abstract (down) 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.
Address
Corporate Author Thesis
Publisher SPIE Place of Publication Editor Fiurásek, J.; Prochazka, I.
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference Photon Counting Applications, Quantum Optics, and Quantum Information Transfer and Processing III
Notes Approved no
Call Number Serial 1387
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Author Kahl, O.; Ferrari, S.; Kovalyuk, V.; Goltsman, G. N.; Korneev, A.; Pernice, W. H. P.
Title Waveguide integrated superconducting single-photon detectors with high internal quantum efficiency at telecom wavelengths Type Journal Article
Year 2015 Publication Sci. Rep. Abbreviated Journal Sci. Rep.
Volume 5 Issue Pages 10941 (1 to 11)
Keywords optical waveguides; waveguide integrated SSPD; waveguide SSPD; nanophotonics
Abstract (down) Superconducting nanowire single-photon detectors (SNSPDs) provide high efficiency for detecting individual photons while keeping dark counts and timing jitter minimal. Besides superior detection performance over a broad optical bandwidth, compatibility with an integrated optical platform is a crucial requirement for applications in emerging quantum photonic technologies. Here we present efficiencies close to unity at 1550nm wavelength. This allows for the SNSPDs to be operated at bias currents far below the critical current where unwanted dark count events reach milli-Hz levels while on-chip detection efficiencies above 70% are maintained. The measured dark count rates correspond to noiseequivalent powers in the 10–19W/Hz–1/2 range and the timing jitter is as low as 35ps. Our detectors are fully scalable and interface directly with waveguide-based optical platforms.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes PMID:26061283; PMCID:PMC4462017 Approved no
Call Number RPLAB @ kovalyuk @ Serial 946
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Author Florya, I. N.; Korneeva, Y. P.; Mikhailov, M. Y.; Devizenko, A. Y.; Korneev, A. A.; Goltsman, G. N.
Title Photon counting statistics of superconducting single-photon detectors made of a three-layer WSi film Type Journal Article
Year 2018 Publication Low Temp. Phys. Abbreviated Journal Low Temp. Phys.
Volume 44 Issue 3 Pages 221-225
Keywords WSi SSPD, SNSPD
Abstract (down) 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.

This work was supported by technical task No. 88 for scientific research at the National Research University “Higher School of Economics,” Grant No. 14.V25.31.0007 from the Ministry of Education and Science of Russia, and the work of G. N. Goltsman was supported by task No. 3.7328.2017/VU of the Ministry of Education and Science of Russia.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1063-777X ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1310
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Author Titova, N; Kardakova, A.; Tovpeko, N; Ryabchun, S.; Mandal, S.; Morozov, D.; Klemencic, G. M.; Giblin, S.R.; Williams, O. A.; Goltsman, G. N.
Title Superconducting diamond films as perspective material for direct THz detectors Type Abstract
Year 2017 Publication Proc. 28th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 28th Int. Symp. Space Terahertz Technol.
Volume Issue Pages 82
Keywords KID, HEB, superconducting diamond films, boron-doped diamond films, Al, TiN, Si substrates, NEP
Abstract (down) Superconducting films with a high resistivity in the normal state have established themselves as the best materials for direct THz radiation sensors, such as kinetic inductance detectors (KIDs) [1] and hot electron bolometers (nano-HEBs) [2]. The primary characteristics of the future instrument such as the sensitivity and the response time are determined by the material parameters such as the electron-phonon (e-ph) interaction time, the electron density and the resistivity of the material. For direct detectors, such as KIDs and nano-HEBs, to provide a high sensitivity and low noise one prefer materials with long e-ph relaxation times and low values of the electron density. As a potential material for THz radiation detection we have studied superconducting diamond films. A significant interest to diamond for the development of electronic devices is due to the evolution of its properties with the boron dopant concentration. At a high boron doping concentration, n B ~5·10 20 cm -3 , diamond has been reported to become a superconducting with T c depending on the doping level. Our previous study of energy relaxation in single-crystalline boron-doped diamond films epitaxially grown on a diamond shows a remarkably slow energy-relaxation at low temperatures. The electron-phonon cooling time varies from 400 ns to 700 ns over the temperature range 2.2 K to 1.7 K [3]. In superconducting materials such as Al and TiN, traditionally used in KIDs, the e-ph cooling times at 1.7 K correspond to ~20 ns [4] and ~100 ns [5], correspondingly. Such a noticeable slow e-ph relaxation in boron-doped diamond, in combination with a low value of carrier density (~10 21 cm -3 ) in comparison with typical metals (~10 23 cm -3 ) and a high normal state resistivity (~1500 μΩ·cm) confirms a potential of superconducting diamond for superconducting bolometers and resonator detectors. However, the price and the small substrate growth are of single crystal diamond limit practical applications of homoepitaxial diamond films. As an alternative way with more convenient technology, one can employ heteroepitaxial diamond films grown on large-size Si substrates. Here we report about measurements of e-ph cooling times in superconducting diamond grown on silicon substrate and discuss our expectations about the applicability of boron-doped diamond films to superconducting detectors. Our estimation of limit value of noise-equivalent power (NEP) and the energy resolution of bolometer made from superconducting diamond is order 10 -17 W/Hz 1/2 at 2 K and the energy resolution is of 0.1 eV that corresponds to counting single-photon up to 15 um. The estimation was obtained by using the film thickness of 70 nm and ρ ~ 1500 μΩ·cm, and the planar dimensions that are chosen to couple bolometer with 75 Ω log-spiral antenna. Although the value of NEP is far yet from what might like to have for certain astronomical applications, we believe that it can be improved by a suitable fabrication process. Also the direct detectors, based on superconducting diamond, will offer low noise performance at about 2 K, a temperature provided by inexpensive close-cycle refrigerators, which provides another practical advantage of development and application of these devices. [1] P.K. Day, et. al, Nature, 425, 817, 2003. [2] J. Wei, et al, Nature Nanotech., 3, 496, 2008. [3] A. Kardakova, et al, Phys. Rev. B, 93, 064506, 2016. [4] P. Santhanam and D. Prober, Phys. Rev. B, 29, 3733, 1984 [5] A. Kardakova, et al, Appl. Phys. Lett, vol. 103, p. 252602, 2013.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1173
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Author Iomdina, E. N.; Seliverstov, S. V.; Teplyakova, K. O.; Jani, E. V.; Pozdniakova, V. V.; Polyakova, O. N.; Goltsman, G. N.
Title Terahertz scanning of the rabbit cornea with experimental UVB-induced damage: in vivo assessment of hydration and its verification Type Journal Article
Year 2021 Publication J. Biomed. Opt. Abbreviated Journal J. Biomed. Opt.
Volume 26 Issue 4 Pages
Keywords medicine; scheimpflug imaging; UVB; confocal microscopy; cornea; optical coherent tomography; rabbit eyes; terahertz radiation
Abstract (down) SIGNIFICANCE: Water content plays a vital role in the normally functioning visual system; even a minor disruption in the water balance may be harmful. Today, no direct method exists for corneal hydration assessment, while it could be instrumental in early diagnosis and control of a variety of eye diseases. The use of terahertz (THz) radiation, which is highly sensitive to water content, appears to be very promising. AIM: To find out how THz scanning parameters of corneal tissue measured by an experimental setup, specially developed for in vivo contactless estimations of corneal reflectivity coefficient (RC), are related to pathological changes in the cornea caused by B-band ultraviolet (UVB) exposure. APPROACH: The setup was tested on rabbit eyes in vivo. Prior to the course of UVB irradiation and 1, 5, and 30 days after it, a series of examinations of the corneal state was made. At the same time points, corneal hydration was assessed by measuring RC. RESULTS: The obtained data confirmed the negative impact of UVB irradiation course on the intensity of tear production and on the corneal thickness and optical parameters. A significant (1.8 times) increase in RC on the 5th day after the irradiation course, followed by a slight decrease on the 30th day after it was revealed. The RC increase measured 5 days after the UVB irradiation course generally corresponded to the increase (by a factor of 1.3) of tear production. RC increase occurred with the corneal edema, which was manifested by corneal thickening (by 18.2% in the middle area and 17.6% in corneal periphery) and an increased volume of corneal tissue (by 17.6%). CONCLUSIONS: Our results demonstrate that the proposed approach can be used for in vivo contactless estimation of the reflectivity of rabbit cornea in the THz range and, thereby, of cornea hydration.
Address National Research University Higher School of Economics, Moscow Institute of Electronics and Mathema, Russia
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1083-3668 ISBN Medium
Area Expedition Conference
Notes PMID:33834684; PMCID:PMC8027227 Approved no
Call Number Serial 1258
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Author Baubert, J.; Salez, M.; Merkel, H.; Pons, P.; Cherednichenko, S.; Lecomte, B.; Drakinsky, V.; Goltsman, G.; Leone, B.
Title IF gain bandwidth of membrane-based NbN hot electron bolometers for SHAHIRA Type Journal Article
Year 2005 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 15 Issue 2 Pages 507-510
Keywords NbN HEB mixers, applications
Abstract (down) SHAHIRA (Submm Heterodyne Array for HIgh-speed Radio Astronomy) is a project supported by the European Space Agency (ESA) and is designed to fly on the SOFIA observatory. A quasi-optic design has been chosen for 2.5/2.7 THz and 4.7 THz, for hydroxyde radical OH, deuterated hydrogen HD and neutral atomic oxygen OI lines observations. Hot electron bolometers (HEBs) have been processed on 1 /spl mu/m thick SiO/sub 2//Si/sub 3/N/sub 4/ stress-less membranes. In this paper we analyse the intermediate frequency (IF) gain bandwidth from the theoretical point of view, and compare it to measurements.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1558-2515 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1468
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Author Tretyakov, Ivan; Kaurova, N.; Voronov, B. M.; Goltsman, G. N.
Title About effect of the temperature operating conditions on the noise temperature and noise bandwidth of the terahertz range NbN hot-electron bolometers Type Abstract
Year 2018 Publication Proc. 29th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 29th Int. Symp. Space Terahertz Technol.
Volume Issue Pages 113
Keywords NbN HEB mixer
Abstract (down) Results of an experimental study of the noise temperature (Tn) and noise bandwidth (NBW) of the superconductor NbN hot-electron bolometer (HEB) mixer as a function of its temperature (Tb) and NbN bridge length are presented. It was determined that the NBW of the mixer is significantly wider at temperatures close to the critical ones (Tc) than are values measured at 4.2 K. The NBW of the mixer measured at the heterodyne frequency of 2.5 THz at temperature Tb close to Tc was ~13 GHz, as compared with 6 GHz at Tb = 4.2 K. This experiment clearly demonstrates the limitation of the thermal flow from the NbN bridge at Tb ≪ Tc for mixers manufactured by the in situ technique. This limitation is close in its nature to the Andreev reflection on the superconductor/metal boundary. In this case, the noise temperature of the studied mixer increased from 1100 to 3800 K.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1313
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Author Tiulina, V.; Iomdina, E.; Goltsman, G.; Seliverstov, S.; Sianosyan, A.; Teplyakova, K.; Rusova, A.; Zaitsev, S.; Zernii, E.; Senin, I.
Title UVB promotes the initiation of uveitic inflammatory and changes in thehydration of the cornea in vivo Type Miscellaneous
Year 2019 Publication FEBS Open Bio Abbreviated Journal FEBS Open Bio
Volume 9 Issue S1 Pages 79
Keywords medicine; scheimpflug imaging; UVB; confocal microscopy; cornea; optical coherent tomography; rabbit eyes; terahertz radiation
Abstract (down) Recently, active research has been conducted in the field of terahertz (THz) scanning of human tissues for non­invasive determination of their hydration level, which haves hown high diagnostic efficiency of this technology in various pathological conditions. Recently, we have developed a laboratory model of the facility for monitoring the state of the water balance of the cornea using THz scanning in vivo, which opens up the possibility of applying this approach in ophthalmology. The aim of the work wasto compare the results of the THz scan of the cornea with its clinical changes using the example of an experimental model of the UV­ induced keratouveitis. Anexperimental study, which included a comprehensive assessment of clinical changes in the cornea of rabbits during keratouveitis induction, revealed a decrease in the stability of the tear film, pathological changes in the corneal epithelium and stroma, as well as its anatomical and optical parameters. Comparison of data obtained in the THz scan of the cornea with tears production, optical coherence tomography and confocal microscopy showed their consistency in all observation periods, which allows us to conclude that the developed laboratory setup works and the feasibility of further research to promote the corneal hydration evaluation technology in clinical practice. Acknowledgements: Research was funded by the RSF, grant number 16­15­00255.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2211-5463 ISBN Medium
Area Expedition Conference
Notes Poster P-01-040 Approved no
Call Number Serial 1276
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Author Elezov, M. S.; Ozhegov, R. V.; Goltsman, G. N.; Makarov, V.; Vinogradov, E. A.; Naumov, A. V.; Gladush, M. G.; Karimullin, K. R.
Title Development of the experimental setup for investigation of latching of superconducting single-photon detector caused by blinding attack on the quantum key distribution system Type Conference Article
Year 2017 Publication EPJ Web Conf. Abbreviated Journal EPJ Web Conf.
Volume 132 Issue Pages 01004 (1 to 2)
Keywords QKD, SSPD, SNSPD
Abstract (down) Recently bright-light control of the SSPD has been demonstrated. This attack employed a “backdoor” in the detector biasing scheme. Under bright-light illumination, SSPD becomes resistive and remains “latched” in the resistive state even when the light is switched off. While the SSPD is latched, Eve can simulate SSPD single-photon response by sending strong light pulses, thus deceiving Bob. We developed the experimental setup for investigation of a dependence on latching threshold of SSPD on optical pulse length and peak power. By knowing latching threshold it is possible to understand essential requirements for development countermeasures against blinding attack on quantum key distribution system with SSPDs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2100-014X ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1327
Permanent link to this record
 
 
Author Elezov, M. S.; Ozhegov, R. V.; Goltsman, G. N.; Makarov, V.
Title Development of the experimental setup for investigation of latching of superconducting single-photon detector caused by blinding attack on the quantum key distribution system Type Conference Article
Year 2017 Publication EPJ Web of Conferences Abbreviated Journal EPJ Web of Conferences
Volume 132 Issue 2 Pages 2
Keywords
Abstract (down) Recently bright-light control of the SSPD has been

demonstrated. This attack employed a “backdoor” in the detector biasing

scheme. Under bright-light illumination, SSPD becomes resistive and

remains “latched” in the resistive state even when the light is switched off.

While the SSPD is latched, Eve can simulate SSPD single-photon response

by sending strong light pulses, thus deceiving Bob. We developed the

experimental setup for investigation of a dependence on latching threshold

of SSPD on optical pulse length and peak power. By knowing latching

threshold it is possible to understand essential requirements for

development countermeasures against blinding attack on quantum key

distribution system with SSPDs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ kovalyuk @ Serial 1116
Permanent link to this record