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Author Elezov, M. S.; Semenov, A. V.; An, P. P.; Tarkhov, M. A.; Goltsman, G. N.; Kardakova, A. I.; Kazakov, A. Y.
Title Investigating the detection regimes of a superconducting single-photon detector Type Journal Article
Year 2013 Publication J. Opt. Technol. Abbreviated Journal J. Opt. Technol.
Volume 80 Issue 7 Pages 435
Keywords SSPD, quantum efficiency
Abstract The detection regimes of a superconducting single-photon detector have been investigated. A technique is proposed for determining the regions in which “pure regimes” predominate. Based on experimental data, the dependences of the internal quantum efficiency on the bias current are determined in the one-, two-, and three-photon detection regimes.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1070-9762 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1172
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Author Vorobyov, V. V.; Kazakov, A. Y.; Soshenko, V. V.; Korneev, A. A.; Shalaginov, M. Y.; Bolshedvorskii, S. V.; Sorokin, V. N.; Divochiy, A. V.; Vakhtomin, Y. B.; Smirnov, K. V.; Voronov, B. M.; Shalaev, V. M.; Akimov, A. V.; Goltsman, G. N.
Title Superconducting detector for visible and near-infrared quantum emitters [Invited] Type Journal Article
Year 2017 Publication Opt. Mater. Express Abbreviated Journal Opt. Mater. Express
Volume 7 Issue 2 Pages 513-526
Keywords SSPD, SNSPD
Abstract Further development of quantum emitter based communication and sensing applications intrinsically depends on the availability of robust single-photon detectors. Here, we demonstrate a new generation of superconducting single-photon detectors specifically optimized for the 500–1100 nm wavelength range, which overlaps with the emission spectrum of many interesting solid-state atom-like systems, such as nitrogen-vacancy and silicon-vacancy centers in diamond. The fabricated detectors have a wide dynamic range (up to 350 million counts per second), low dark count rate (down to 0.1 counts per second), excellent jitter (62 ps), and the possibility of on-chip integration with a quantum emitter. In addition to performance characterization, we tested the detectors in real experimental conditions involving nanodiamond nitrogen-vacancy emitters enhanced by a hyperbolic metamaterial.
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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 2159-3930 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1234
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Author Moshkova, M.; Divochiy, A.; Morozov, P.; Vakhtomin, Y.; Antipov, A.; Zolotov, P.; Seleznev, V.; Ahmetov, M.; Smirnov, K.
Title High-performance superconducting photon-number-resolving detectors with 86% system efficiency at telecom range Type Journal Article
Year 2019 Publication J. Opt. Soc. Am. B Abbreviated Journal J. Opt. Soc. Am. B
Volume 36 Issue 3 Pages B20
Keywords NbN PNR SSPD, SNSPD
Abstract The use of improved fabrication technology, highly disordered NbN thin films, and intertwined section topology makes it possible to create high-performance photon-number-resolving superconducting single-photon detectors (PNR SSPDs) that are comparable to conventional single-element SSPDs at the telecom range. The developed four-section PNR SSPD has simultaneously an 86±3% system detection efficiency, 35 cps dark count rate, ∼2 ns dead time, and maximum 90 ps jitter. An investigation of the PNR SSPD’s detection efficiency for multiphoton events shows good uniformity across sections. As a result, such a PNR SSPD is a good candidate for retrieving the photon statistics for light sources and quantum key distribution systems.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0740-3224 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1225
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Author Neroev, V. V.; Iomdina, E. N.; Khandzhyan, A. T.; Khodzhabekyan, N. V.; Sengaeva, M. D.; Ivanova, A. V.; Seliverstov, S. V.; Teplyakova, K. O.; Goltsman, G. N.
Title Experimental study of the effect of corneal hydration and its biomechanical properties on the results of photorefractive keratectomy Type Journal Article
Year 2021 Publication Vestn. Oftalmol. Abbreviated Journal Vestn. Oftalmol.
Volume 137 Issue 3 Pages 68-75
Keywords THz scanning, cornea, photorefractive keratectomy, medicine
Abstract Water content in the cornea may affect the outcome of its excimer laser ablation, especially in presbyopic patients with myopic refraction. This hypothesis can be tested by scanning the cornea in the terahertz (THz) range to determine its hydration level.

Purpose: To study the effect of hydration of the cornea determined by non-contact THz scanning and its biomechanical parameters on the results of photorefractive keratectomy (PRK) in an experiment.

Material and methods: PRK was performed using the Nidek EC-5000 QUEST excimer laser on 8 rabbit eyes. Corneal hydration was evaluated by determining the reflection coefficient (RC) in the THz electromagnetic radiation range before PRK, after 3-5 days, and after 1, 2, 3, and 4 months. Clinical examination included autorefractometry, assessment of corneal thickness and other anatomical and optical parameters of the anterior eye segment (Galilei G6, Ziemer Ophthalmic Systems AG 6.0.2, Switzerland), measurement of corneal hysteresis (CH) and corneal resistance factor (CRF) using the Ocular Response Analyzer (ORA; Reichert, USA), as well as tear production (Schirmer test).

Results: The initial water content in the cornea has a significant effect on the thickness of the removed layer, i.e. on the PRK effect, with correlation coefficient of Rs= -0.976 (p<0.01). The correlation between CH and the ablation depth is less pronounced (Rs=0.643), and CRF had no correlation with it (Rs= -0.089). Biomechanical indicators of the cornea depend on its hydration: changes in CH and CRF after excimer laser ablation qualitatively coincide with changes in RC, the correlation coefficient between RC and the initial value of CH is R= -0.619 (moderate negative correlation).

Conclusion: THz scanning is an effective non-contact technology for monitoring corneal hydration level. The mismatch of the hypoeffect of keratorefractive excimer laser intervention planned for patients with presbyopia with the actual outcome can be caused by individual decrease in the initial water content in the cornea.
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Publisher Place of Publication Editor
Language Russian Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1794
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Author Tikhonov, V. V.; Boyarskii, D. A.; Polyakova, O. N.; Dzardanov, A. L.; Goltsman, G. N.
Title Radiophysical and dielectric properties of ore minerals in 12--145 GHz frequency range Type Journal Article
Year 2010 Publication PIER B Abbreviated Journal PIER B
Volume 25 Issue Pages 349-367
Keywords complex permittivity, ore minerals
Abstract The paper discusses a retrieval technique of complex permittivity of ore minerals in frequency ranges of 12--38 GHz and 77--145 GHz. The method is based on measuring frequency dependencies of transmissivity and reflectivity of plate-parallel mineral samples. In the 12--38 GHz range, the measurements were conducted using a panoramic standing wave ratio and attenuation meter. In the 77--145 GHz range, frequency dependencies of transmissivity and reflectivity were obtained using millimeter-band spectrometer with backward-wave oscillators. The real and imaginary parts of complex permittivity of a mineral were determined solving an equation system for frequency dependencies of transmissivity and reflectivity of an absorbing layer located between two dielectric media. In the course of the work, minerals that are primary ores in iron, zinc, copper and titanium mining were investigated: magnetite, hematite, sphalerite, chalcopyrite, pyrite, and ilmenite.
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Area Expedition Conference
Notes Approved no
Call Number RPLAB @ gujma @ Serial 639
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Author Słysz, W.; Węgrzecki, M.; Bar, J.; Grabiec, P.; Gol'tsman, G. N.; Verevkin, A.; Sobolewski, R.
Title NbN superconducting single-photon detector coupled with a communication fiber Type Journal Article
Year 2005 Publication Elektronika : konstrukcje, technologie, zastosowania Abbreviated Journal
Volume 46 Issue 6 Pages 51-52
Keywords NbN SSPD, SNSPD
Abstract We present novel superconducting single-photon detectors (SSPDs), ba­sed on ultrathin NbN films, designed for fiber-based quantum communica­tions (lambda = 1.3 žm and 1.55 žm). For fiber-based operation, our SSPDs contain a special micromechanical construction integrated with the NbN structure, which enables efficient and mechanically very stabile fiber coupling. The detectors combine GHz counting rate, high quantum efficiency and very low level of dark counts. At 1.3 – 1.55 žm wavelength range our detector exhibits a quantum efficiency up to 10%.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Polish Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1481
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Author Semenov, A.; Engel, A.; Il'in, K.; Gol'tsman, G.; Siegel, M.; Hübers, H.-W.
Title Ultimate performance of a superconducting quantum detector Type Journal Article
Year 2003 Publication Eur. Phys. J. Appl. Phys. Abbreviated Journal Eur. Phys. J. Appl. Phys.
Volume 21 Issue 3 Pages 171-178
Keywords NbN SSPD, SNSPD
Abstract We analyze the ultimate performance of a superconducting quantum detector in order to meet requirements for applications in near-infrared astronomy and X-ray spectroscopy. The detector exploits a combined detection mechanism, in which avalanche quasiparticle multiplication and the supercurrent jointly produce a voltage response to a single absorbed photon via successive formation of a photon-induced and a current-induced normal hotspot in a narrow superconducting strip. The response time of the detector should increase with the photon energy providing energy resolution. Depending on the superconducting material and operation conditions, the cut-off wavelength for the single-photon detection regime varies from infrared waves to visible light. We simulated the performance of the background-limited infrared direct detector and X-ray photon counter utilizing the above mechanism. Low dark count rate and intrinsic low-frequency cut-off allow for realizing a background limited noise equivalent power of 10−20 W Hz−1/2 for a far-infrared direct detector exposed to 4-K background radiation. At low temperatures, the intrinsic response time of the counter is rather determined by diffusion of nonequilibrium electrons than by the rate of energy transfer to phonons. Therefore, thermal fluctuations do not hamper energy resolution of the X-ray photon counter that should be better than 10−3 for 6-keV photons. Comparison of new data obtained with a Nb based detector and previously reported results on NbN quantum detectors support our estimates of ultimate detector performance.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1286-0042 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 534
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Author Lobanov, Y. V.; Vakhtomin, Y. B.; Pentin, I. V.; Khabibullin, R. A.; Shchavruk, N. V.; Smirnov, K. V.; Silaev, A. A.
Title Characterization of the THz quantum cascade laser using fast superconducting hot electron bolometer Type Journal Article
Year 2018 Publication EPJ Web Conf. Abbreviated Journal EPJ Web Conf.
Volume 195 Issue Pages 04004 (1 to 2)
Keywords NbN HEB, QCL
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Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2100-014X ISBN Medium
Area Expedition Conference 3rd International Conference “Terahertz and Microwave Radiation: Generation, Detection and Applications” (TERA-2018)
Notes Approved no
Call Number Serial 1808
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Author Aksaev, E. E.; Gershenzon, E.M.; Gol'tsman, G. N.; Mirskij, G. I.; Semenov, A. D.
Title Submillimetric spectrometer-relaxometer based on backward-wave tubes with picosecond time resolution Type Journal Article
Year 1991 Publication Pribory i Tekhnika Eksperimenta Abbreviated Journal Pribory i Tekhnika Eksperimenta
Volume 34 Issue 2 Pages 125-131
Keywords BWO, applications
Abstract The high-sensitive automatic spectrometer-relaxometer based on backward-wave tubes in the range of 4÷0.25 mm was described permitting to study the response kinetics of sample under investigation in any point of this range with the resolution time of 10-11 s. The relaxation measurements were conducted using oscillation beats of two adequate tubes, the frequency of one of them was fixed, while that of the other one was changeable. The amplitude-frequency characteristic of the response under the conditions of synchronous reception was recorded at beat frequency variation from 107 to 1010 Hz. The high sensitivity was reached by decreasing the device recording band down to 100 Hz in the whole measuring range.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0032-8162 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1683
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Author Kawamura, J.; Hunter, T. R.; Tong, C. Y. E.; Blundell, R.; Papa, D. C.; Patt, F.; Peters, W.; Wilson, T.; Henkel, C.; Goltsman, G.; Gershenzon, E.
Title Ground-based terahertz CO spectroscopy towards Orion Type Journal Article
Year 2002 Publication A&A Abbreviated Journal A&A
Volume 394 Issue 1 Pages 271-274
Keywords HEB mixers, applications
Abstract Using a superconductive hot-electron bolometer heterodyne receiver on the 10-m Heinrich Hertz Telescope on Mount Graham, Arizona, we have obtained velocity-resolved 1.037 THz CO () spectra toward several positions along the Orion Molecular Cloud (OMC-1) ridge. We confirm the general results of prior observations of high-J CO lines that show that the high temperature, , high density molecular gas, , is quite extended, found along a ~ region centered on BN/KL. However, our observations have significantly improved angular resolution, and with a beam size of we are able to spatially and kinematically discriminate the emission originating in the extended quiescent ridge from the very strong and broadened emission originating in the compact molecular outflow. The ridge emission very close to the BN/KL region appears to originate from two distinct clouds along the line of sight with and ≈ . The former component dominates the emission to the south of BN/KL and the latter to the north, with a turnover point coincident with or near BN/KL. Our evidence precludes a simple rotation of the inner ridge and lends support to a model in which there are multiple molecular clouds along the line of sight towards the Orion ridge.
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Series Editor Series Title Abbreviated Series Title
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ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 322
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