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Author 0kunev, 0.; Dzardanov, A.; Ekstrom, H.; Jacobsson, S.; Kollberg, E.; Gol'tsman, G.; Gershenzon, E. url  openurl
  Title NbN hot electron waveguide mixer for 100 GHz operation Type Conference Article
  Year 1994 Publication Proc. 5th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 5th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages 214-224  
  Keywords waveguide NbN HEB mixers  
  Abstract NbN is a promising superconducting material used to develope hot- electron superconducting mixers with an IF bandwidth over 1 GHz. In the 100 GHz frequency range, the following parameters were obtained for NbN films 50 A thick: the noise temperature of the receiver (DSB) 1000 K; the conversion losses 10 d13, the IF bandwidth 1 GHz; the local oscillator power 1 /LW. An increase of NbN film thickness up to 80-100 A and increase of working temperature up to 7-8 K, and a better mixer matching may allow to broader the IF band up to 3 Gllz, to reduce the conversion losses down to 3-5 dB and the noise tempera- ture down to 200-300 K.  
  Address  
  Corporate Author (up) 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 1644  
Permanent link to this record
 
 
Author Gousev, Y. P.; Semenov, A. D.; Gol'tsman, G. N.; Sergeev, A. V.; Gershenzon, E. M. url  doi
openurl 
  Title Electron-phonon interaction in disordered NbN films Type Journal Article
  Year 1994 Publication Phys. B Condens. Mat. Abbreviated Journal Phys. B Condens. Mat.  
  Volume 194-196 Issue Pages 1355-1356  
  Keywords NbN films  
  Abstract Electron-phonon interaction time has been investigated in disordered films of NbN. A temperatures below 5.5 K tau_eph ~ T -1"6 which is attributed to the renormalisation of phonon spectrum in thin films.  
  Address  
  Corporate Author (up) Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0921-4526 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1649  
Permanent link to this record
 
 
Author Gol’tsman, G. N.; Gershenzon, E. M. url  doi
openurl 
  Title High speed hot-electron superconducting bolometer Type Conference Article
  Year 1993 Publication Proc. SPIE Abbreviated Journal Proc. SPIE  
  Volume 2104 Issue Pages 181-182  
  Keywords NbN HEb, Nb, Al  
  Abstract Physical limitation of response time of a superconducting bolometer as well as the nature of non-equilibrium detection of radiation have been investigated for Al, Nb and NbN thin films in spectral range from submillimeter to near-infraredwavelengths [1,2]. In the case of ideal heat removal from the film with the f_‘. 100A thickness the detection mechanism is an electron heating effect that is not selective to radiation wavelength in a very broad range. The response time ofan electron heating bolometer is determined by an electron-phonon interaction time. This time is of about 10 ns, 0.5 ns and 20 ps for Al, Nb, and NbN correspondingly near the critical temperature of the superconducting film. Thesensitive area of the bolometer consists of a number of narrow strips (with awidth of 1µm) connected in parallel to contact pads; these pads together witha sapphire substrate and a ground plate represent the microstrip transmissionline with an impedance of 50 Q.  
  Address  
  Corporate Author (up) Thesis  
  Publisher SPIE Place of Publication Editor Birch, J.R.; Parker, T.J.  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference 18th International Conference on Infrared and Millimeter Waves  
  Notes Approved no  
  Call Number Serial 1652  
Permanent link to this record
 
 
Author Voronov, B. M.; Gershenzon, E. M.; Gol'tsman, G. N.; Gogidze, I. G.; Gusev, Yu. P.; Zorin, M. A.; Sejdman, L. A.; Semenov, A. D. url  openurl
  Title Picosecond range detector base on superconducting niobium nitride film sensitive to radiation in spectral range from millimeter waves up to visible light Type Journal Article
  Year 1992 Publication Sverkhprovodimost': Fizika, Khimiya, Tekhnika Abbreviated Journal Sverkhprovodimost': Fizika, Khimiya, Tekhnika  
  Volume 5 Issue 5 Pages 955-960  
  Keywords NbN HEB detectors  
  Abstract Fast-operating picosecond detector of electromagnetical radiation is developed on the basis of fine superconducting film of niobium nitride with high sensitivity within spectral range from millimetric waves up to visible light. Detector sensitive element represents structure covering narrow parallel strips with micron sizes included in the rupture of microstrip line. Detecting ability of the detector and time constant measured using amplitude-simulated radiation of reverse wave tubes and pulse radiation of picosecond gas and solid-body lasers, constitute D*≅1010 W-1·cm·Hz-1/2 and τ≤5 ps respectively, at 10 K temperature. The expected value of time constant of the detector at 10 K obtained via extrapolation of directly measured dependence that is, τ ∝ τ-1, constitutes 20 ps. Experimental data demonstrate that detection mechanism is linked with electron heating effect.  
  Address  
  Corporate Author (up) Thesis  
  Publisher Place of Publication Editor  
  Language Russian Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0131-5366 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1670  
Permanent link to this record
 
 
Author Budyanskij, M. Ya.; Sejdman, L. A.; Voronov, B. M.; Gubkina, T. O. url  openurl
  Title Increase of reproducibility in production of superconducting thin films of niobium nitride Type Journal Article
  Year 1992 Publication Sverkhprovodimost': Fizika, Khimiya, Tekhnika Abbreviated Journal Sverkhprovodimost': Fizika, Khimiya, Tekhnika  
  Volume 5 Issue 10 Pages 1950-1954  
  Keywords NbN films  
  Abstract Technique to control the composition of gas medium in the reactive magnetron discharge and the composition of the deposited films of niobium nitride using electrical parameters of discharge only, in particular, by δU = Up – Uar value at contant stabilized discharge current is described. Technique to select optimal condition for deposition of niobium nitride films when the films have composition meeting chemical formula, is suggested. Thin films of niobium nitride with up to 7 nm thickness and with rather high temperature of transition into superconducting state Tk > 10 K) and with low width of transition (δ < 0.6 K), are obtained. It is determined, that substrate material and dielectric sublayer do not affect. Tk value, while difference in coefficients of thermal expansion of substrate and of film affects δTk value.  
  Address  
  Corporate Author (up) Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0131-5366 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1675  
Permanent link to this record
 
 
Author Gol’tsman, G.N. url  openurl
  Title Overview of recent results for superconducting NbN terahertz and optical detectors and mixers Type Miscellaneous
  Year 2014 Publication SM2 – Seminar on Terahertz Photonics Abbreviated Journal  
  Volume Issue Pages 0562  
  Keywords NbN SSPD, SNSPD, HEB  
  Abstract We present our recent achievements in the development of sensitive and ultrafast thin-film superconducting sensors: hot-electron bolometers (HEB), HEB-mixers for terahertz range and infrared single-photon counters. These sensors have already demonstrated a performance that makes them devices-of-choice for many terahertz and optical applications.  
  Address  
  Corporate Author (up) 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 1746  
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Author Pentin, Ivan; Finkel, Matvey; Maslennikov, Sergey; Vakhtomin, Yuri; Smirnov, Konstantin; Kaurova, Nataliya; Goltsman, Gregory url  openurl
  Title Superconducting hot-electron-bolometer mixers for the mid-IR Type Journal Article
  Year 2017 Publication Rus. J. Radio Electron. Abbreviated Journal Rus. J. Radio Electron.  
  Volume Issue 10 Pages  
  Keywords IR NbN HEB mixers  
  Abstract The work presents the result of development of the NbN superconducting hot-electron-bolometer (HEB) mixer. The sensitive element of the mixer is directly coupled to mid-IR radiation, and doesn’t have planar metallic antenna. Investigations of noise characteristics of NbN HEB mixer were performed at the frequency 28.4 THz (λ = 10.6 µm) by using gas-discharge CW CO2-laser without consideration of optical and electrical losses in the heterodyne receiver. The noise temperature of NbN HEB mixer with the size of the sensitive element 10 µm × 10 µm was 2320 K (~ 1.5hν/kB) at the heterodyne frequency of 28.4 THz. The noise temperature was determined by measuring the Y-factor taking into account the term which describes fluctuations of zero-point oscillations in accordance with the fluctuation-dissipation theorem of Calle-Welton. Isothermal method was used to estimate the absorbed heterodyne radiation power which was 9 µW at the optimal operating point for the minimum noise temperature of NbN HEB mixer.  
  Address  
  Corporate Author (up) Thesis  
  Publisher Place of Publication Editor  
  Language Russian Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1684-1719 ISBN Medium  
  Area Expedition Conference  
  Notes http://jre.cplire.ru/jre/oct17/9/abstract.html (Russian) Гетеродинный приемник со сверхпроводниковым смесителем на эффекте электронного разогрева для среднего инфракрасного диапазона Approved no  
  Call Number Serial 1747  
Permanent link to this record
 
 
Author Zhang, J.; Verevkin, A.; Slysz, W.; Chulkova, G.; Korneev, A.; Lipatov, A.; Okunev, O.; Gol’tsman, G. N.; Sobolewski, Roman url  doi
openurl 
  Title Time-resolved characterization of NbN superconducting single-photon optical detectors Type Conference Article
  Year 2017 Publication Proc. SPIE Abbreviated Journal Proc. SPIE  
  Volume 10313 Issue Pages 103130F (1 to 3)  
  Keywords NbN SSPD, SNSPD  
  Abstract NbN superconducting single-photon detectors (SSPDs) are very promising devices for their picosecond response time, high intrinsic quantum efficiency, and high signal-to-noise ratio within the radiation wavelength from ultraviolet to near infrared (0.4 gm to 3 gm) [1-3]. The single photon counting property of NbN SSPDs have been investigated thoroughly and a model of hotspot formation has been introduced to explain the physics of the photon- counting mechanism [4-6]. At high incident flux density (many-photon pulses), there are, of course, a large number of hotspots simultaneously formed in the superconducting stripe. If these hotspots overlap with each other across the width w of the stripe, a resistive barrier is formed instantly and a voltage signal can be generated. We assume here that the stripe thickness d is less than the electron diffusion length, so the hotspot region can be considered uniform. On the other hand, when the photon flux is so low that on average only one hotspot is formed across w at a given time, the formation of the resistive barrier will be realized only when the supercurrent at sidewalks surpasses the critical current (jr) of the superconducting stripe [1]. In the latter situation, the formation of the resistive barrier is associated with the phase-slip center (PSC) development. The effect of PSCs on the suppression of superconductivity in nanowires has been discussed very recently [8, 9] and is the subject of great interest.  
  Address  
  Corporate Author (up) Thesis  
  Publisher SPIE Place of Publication Editor Armitage, J. C.  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference Opto-Canada: SPIE Regional Meeting on Optoelectronics, Photonics, and Imaging, 2002, Ottawa, Ontario, Canada  
  Notes Downloaded from http://www2.ece.rochester.edu/projects/ufqp/PDF/2002/213NbNTimeOPTO_b.pdf This artcle was published in 2017 with only first author indicated (Zhang, J.). There were 8 more authors! Approved no  
  Call Number Serial 1750  
Permanent link to this record
 
 
Author Verevkin, A.; Zhang, J.; Pearlman, A.; Slysz, W.; Sobolewski, Roman; Korneev, A.; Kouminov, P.; Okunev, O.; Chulkova, G.; Gol'tsman, G. url  openurl
  Title Ultimate sensitivity of superconducting single-photon detectors in the visible to infrared range Type Miscellaneous
  Year 2004 Publication ResearchGate Abbreviated Journal ResearchGate  
  Volume Issue Pages  
  Keywords NbN SSPD, SNSPD  
  Abstract We present our quantum efficiency (QE) and noise equivalent power (NEP) measurements of the meandertype ultrathin NbN superconducting single-photon detector in the visible to infrared radiation range. The nanostructured devices with 3.5-nm film thickness demonstrate QE up to~ 10% at 1.3–1.55 µm wavelength, and up to 20% in the entire visible range. The detectors are sensitive to infrared radiation with the wavelengths down to~ 10 µm. NEP of about 2× 10-18 W/Hz1/2 was obtained at 1.3 µm wavelength. Such high sensitivity together with GHz-range counting speed, make NbN photon counters very promising for efficient, ultrafast quantum communications and another applications. We discuss the origin of dark counts in our devices and their ultimate sensitivity in terms of the resistive fluctuations in our superconducting nanostructured devices.  
  Address  
  Corporate Author (up) 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 Not attributed to any publisher! File name: PR9VervekinSfin_f.doc; Author: JAOLEARY; Last modification date: 2004-02-26 Approved no  
  Call Number Serial 1751  
Permanent link to this record
 
 
Author Baeva, E. M.; Titova, N. A.; Veyrat, L.; Sacépé, B.; Semenov, A. V.; Goltsman, G. N.; Kardakova, A. I.; Khrapai, V. S. url  doi
openurl 
  Title Thermal relaxation in metal films limited by diffuson lattice excitations of amorphous substrates Type Journal Article
  Year 2021 Publication Phys. Rev. Applied Abbreviated Journal Phys. Rev. Applied  
  Volume 15 Issue 5 Pages 054014  
  Keywords InOx, Au/Ni, NbN films  
  Abstract We examine the role of a silicon-based amorphous insulating substrate in the thermal relaxation in thin NbN, InOx, and Au/Ni films at temperatures above 5 K. The samples studied consist of metal bridges on an amorphous insulating layer lying on or suspended above a crystalline substrate. Noise thermometry is used to measure the electron temperature Te of the films as a function of Joule power per unit area P2D. In all samples, we observe a P2D∝Tne dependence, with exponent n≃2, which is inconsistent with both electron-phonon coupling and Kapitza thermal resistance. In suspended samples, the functional dependence of P2D(Te) on the length of the amorphous insulating layer is consistent with the linear temperature dependence of the thermal conductivity, which is related to lattice excitations (diffusons) for a phonon mean free path shorter than the dominant phonon wavelength. Our findings are important for understanding the operation of devices embedded in amorphous dielectrics.  
  Address  
  Corporate Author (up) Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2331-7019 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1769  
Permanent link to this record
 
 
Author Shcherbatenko, M.; Elezov, M.; Manova, N.; Sedykh, K.; Korneev, A.; Korneeva, Y.; Dryazgov, M.; Simonov, N.; Feimov, A.; Goltsman, G.; Sych, D. url  doi
openurl 
  Title Single-pixel camera with a large-area microstrip superconducting single photon detector on a multimode fiber Type Journal Article
  Year 2021 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.  
  Volume 118 Issue 18 Pages 181103  
  Keywords NbN SSPD, SNSPD  
  Abstract High sensitivity imaging at the level of single photons is an invaluable tool in many areas, ranging from microscopy to astronomy. However, development of single-photon sensitive detectors with high spatial resolution is very non-trivial. Here we employ the single-pixel imaging approach and demonstrate a proof-of-principle single-pixel single-photon imaging setup. We overcome the problem of low light gathering efficiency by developing a large-area microstrip superconducting single photon detector coupled to a multi-mode optical fiber interface. We show that the setup operates well in the visible and near infrared spectrum, and is able to capture images at the single-photon level.

We thank Philipp Zolotov and Pavel Morozov for NbN film fabrication, ARC coating, and fiber coupling of the detector. We also thank Swabian Instruments GmbH and Dr. Helmut Fedder personally for the kindly provided experimental equipment (Time Tagger Ultra 8). The work in the part of SNSPD research and development was supported by the Russian Foundation for Basic Research Project No. 18-29-20100. The work in the part of the optical setup and imaging was supported by Russian Foundation for Basic Research Project No. 20-32-51004.		  
  Address  
  Corporate Author (up) Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1770  
Permanent link to this record
 
 
Author Korneev, A. A. url  doi
openurl 
  Title Superconducting NbN microstrip single-photon detectors Type Abstract
  Year 2021 Publication Proc. Quantum Optics and Photon Counting Abbreviated Journal Proc. Quantum Optics and Photon Counting  
  Volume 11771 Issue Pages  
  Keywords NbN SSPD, SNSPD  
  Abstract 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.  
  Address  
  Corporate Author (up) Thesis  
  Publisher SPIE Place of Publication Editor Prochazka, I.; Štefaňák, M.; Sobolewski, R.; Gábris, A.  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference Quantum Optics and Photon Counting; SPIE Optics + Optoelectronics, 2021, Online Only  
  Notes Approved no  
  Call Number Serial 1784  
Permanent link to this record
 
 
Author Manova, N. N.; Simonov, N. O.; Korneeva, Y. P.; Korneev, A. A. url  doi
openurl 
  Title Developing of NbN films for superconducting microstrip single-photon detector Type Conference Article
  Year 2020 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.  
  Volume 1695 Issue Pages 012116 (1 to 5)  
  Keywords NbN SSPD, SNSPD, NbN films  
  Abstract We optimized NbN films on a Si substrate with a buffer SiO2 layer to produce superconducting microstrip single-photon detectors with saturated dependence of quantum efficiency (QE) versus normalized bias current. We varied thickness of films and observed the maximum QE saturation for device based on the thinner film with the lowest ratio RS300/RS20.  
  Address  
  Corporate Author (up) Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1742-6588 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1786  
Permanent link to this record
 
 
Author Polyakova, M. I.; Korneev, A. A.; Semenov, A. V. url  doi
openurl 
  Title Comparison single- and double- spot detection efficiencies of SSPD based to MoSi and NbN films Type Conference Article
  Year 2020 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.  
  Volume 1695 Issue Pages 012146 (1 to 3)  
  Keywords NbN SSPD, SNSPD, MoSi  
  Abstract In this work, we present results of quantum detector tomography of superconducting single photon detector (SSPD) based on MoSi film, and compare them with previously reported data on NbN. We find that for both materials hot spot interaction length coincides with the strip width, and the dependence of single and double-spot detection efficiencies on bias current are compatible with sufficiently large hot-spot size, approaching the strip width.  
  Address  
  Corporate Author (up) Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1742-6588 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1787  
Permanent link to this record
 
 
Author Vodolazov, D. Y.; Manova, N. N.; Korneeva, Y. P.; Korneev, A. A. url  doi
openurl 
  Title Timing jitter in NbN superconducting microstrip single-photon detector Type Journal Article
  Year 2020 Publication Phys. Rev. Applied Abbreviated Journal Phys. Rev. Applied  
  Volume 14 Issue 4 Pages 044041 (1 to 8)  
  Keywords NbN SSPD, SNSPD  
  Abstract We experimentally study timing jitter of single-photon detection by NbN superconducting strips with width w ranging from 190 nm to 3μm. We find that timing jitter of both narrow (190 nm) and micron-wide strips is about 40 ps at currents where internal detection efficiency η saturates and it is close to our instrumental jitter. We also calculate intrinsic timing jitter in wide strips using the modified time-dependent Ginzburg-Landau equation coupled with a two-temperature model. We find that with increasing width the intrinsic timing jitter increases and the effect is most considerable at currents where a rapid growth of η changes to saturation. We relate it with complicated vortex and antivortex dynamics, which depends on a photon’s absorption site across the strip and its width. The model also predicts that at current close to depairing current the intrinsic timing jitter of a wide strip could be about ℏ/kBTc (Tc is a critical temperature of superconductor), i.e., the same as for a narrow strip.  
  Address  
  Corporate Author (up) Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2331-7019 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1788  
Permanent link to this record
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