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Author (up) Sidorova, M.; Semenov, A.; Hübers, H.-W.; Kuzmin, A.; Doerner, S.; Ilin, K.; Siegel, M.; Charaev, I.; Vodolazov, D.
Title Timing jitter in photon detection by straight superconducting nanowires: Effect of magnetic field and photon flux Type Journal Article
Year 2018 Publication Phys. Rev. B Abbreviated Journal Phys. Rev. B
Volume 98 Issue 13 Pages 134504 (1 to 14)
Keywords SNSPD, NbN namowires
Abstract We studied the effects of the external magnetic field and photon flux on timing jitter in photon detection by straight superconducting NbN nanowires. At two wavelengths 800 and 1560 nm, statistical distribution in the appearance times of photon counts exhibits Gaussian shape at small times and an exponential tail at large times. The characteristic exponential time is larger for photons with smaller energy and increases with external magnetic field while variations in the Gaussian part of the distribution are less pronounced. Increasing photon flux drives the nanowire from the discrete quantum detection regime to the uniform bolometric regime that averages out fluctuations of the total number of nonequilibrium electrons created by the photon and drastically reduces jitter. The difference between standard deviations of Gaussian parts of distributions for these two regimes provides the measure for the strength of electron-number fluctuations; it increases with the photon energy. We show that the two-dimensional hot-spot detection model explains qualitatively the effect of magnetic field.
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 2469-9950 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1842
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Author (up) Sidorova, M.; Semenov, Alexej D.; Hübers, H.-W.; Ilin, K.; Siegel, M.; Charaev, I.; Moshkova, M.; Kaurova, N.; Goltsman, G. N.; Zhang, X.; Schilling, A.
Title Electron energy relaxation in disordered superconducting NbN films Type Journal Article
Year 2020 Publication Phys. Rev. B Abbreviated Journal Phys. Rev. B
Volume 102 Issue 5 Pages 054501 (1 to 15)
Keywords NbN SSPD, SNSPD, HEB, bandwidth, relaxation time
Abstract We report on the inelastic-scattering rate of electrons on phonons and relaxation of electron energy studied by means of magnetoconductance, and photoresponse, respectively, in a series of strongly disordered superconducting NbN films. The studied films with thicknesses in the range from 3 to 33 nm are characterized by different Ioffe-Regel parameters but an almost constant product qTl (qT is the wave vector of thermal phonons and l is the elastic mean free path of electrons). In the temperature range 14–30 K, the electron-phonon scattering rates obey temperature dependencies close to the power law 1/τe−ph∼Tn with the exponents n≈3.2–3.8. We found that in this temperature range τe−ph and n of studied films vary weakly with the thickness and square resistance. At 10 K electron-phonon scattering times are in the range 11.9–17.5 ps. The data extracted from magnetoconductance measurements were used to describe the experimental photoresponse with the two-temperature model. For thick films, the photoresponse is reasonably well described without fitting parameters, however, for thinner films, the fit requires a smaller heat capacity of phonons. We attribute this finding to the reduced density of phonon states in thin films at low temperatures. We also show that the estimated Debye temperature in the studied NbN films is noticeably smaller than in bulk material.
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 2469-9950 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1266
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Author (up) Yagoubov, P.; Hübers, H.-W.; Gol’tsman, G.; Semenov, A.; Gao, J.; Hoogeveen, R.; de Graauw, T.; Birk, M.; Selig, A.; de Korte, P.
Title Hot-electron bolometer mixers – technology for far-infrared heterodyne instruments in future atmospheric chemistry missions Type Conference Article
Year 2001 Publication Proc. 3rd Int. Symp. Submillimeter Wave Earth Observation From Space Abbreviated Journal Proc. 3rd Int. Symp. Submillimeter Wave Earth Observation From Space
Volume Issue Pages 57-69
Keywords HEB mixers
Abstract
Address Delmenhorst
Corporate Author Thesis
Publisher Logos-Verlag Place of Publication Editor Buehler, S.; Berlin
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN 3-89722-700-2 Medium
Area Expedition Conference International Symposium on Submillimeter Wave Earth Observation from Space, ISSMWEOS01
Notes Approved no
Call Number Serial 1549
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Author (up) Yagoubov, P.; Kroug, M.; Merkel, H.; Kollberg, E.; Hübers, H.-W.; Schubert, J.; Schwaab, G.; Gol'tsman, G.; Gershenzon, E.
Title NbN hot electron bolometric mixers at frequencies between 0.7 and 3.1 THz Type Conference Article
Year 1999 Publication Proc. 10th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 10th Int. Symp. Space Terahertz Technol.
Volume Issue Pages 238-246
Keywords NbN HEB mixers
Abstract The performance of NbN based phonon-cooled Hot Electron Bolometric (HEB) quasioptical mixers is investigated in the 0.7-3.1 THz frequency range. The devices are made from a 3.5-4 nm thick NbN film on high resistivity Si and integrated with a planar spiral antenna on the same substrate. The length of the bolometer microbridge is 0.1- 0.2 gm, the width is 1-2 gm. The best results of the DSB receiver noise temperature measured at 1.5 GHz intermediate frequency are: 800 K at 0.7 THz, 1100 K at 1.6 THz, 2000 K at 2.5 THz and 4200 K at 3.1 THz. The measurements were performed with a far infrared laser as the local oscillator (LO) source. The estimated LO power required is less than 500 nW at the receiver input. First results on the spiral antenna polarization measurements are reported.
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 1575
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