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Author Vodolazov, D. Y.; Korneeva, Y. P.; Semenov, A. V.; Korneev, A. A.; Goltsman, G. N.
Title Vortex-assisted mechanism of photon counting in a superconducting nanowire single-photon detector revealed by external magnetic field Type Journal Article
Year (up) 2015 Publication Phys. Rev. B Abbreviated Journal Phys. Rev. B
Volume 92 Issue 10 Pages 104503 (1 to 9)
Keywords SSPD, SNSPD
Abstract We use an external magnetic field to probe the detection mechanism of a superconducting nanowire single-photon detector. We argue that the hot belt model (which assumes partial suppression of the superconducting order parameter Δ across the whole width of the superconducting nanowire after absorption of the photon) does not explain observed weak-field dependence of the photon count rate (PCR) for photons with λ=450nm and noticeable decrease of PCR (with increasing the magnetic field) in a range of the currents for photons with wavelengths λ=450–1200nm. Found experimental results for all studied wavelengths can be explained by the vortex hot spot model (which assumes partial suppression of Δ in the area with size smaller than the width of the nanowire) if one takes into account nucleation and entrance of the vortices to the photon induced hot spot and their pinning by the hot spot with relatively large size and strongly suppressed Δ.
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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 1098-0121 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1343
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Author Elezov, M. S.; Ozhegov, R. V.; Kurochkin, Y. V.; Goltsman, G. N.; Makarov, V. S.; Samartsev, V. V.; Vinogradov, E. A.; Naumov, A. V.; Karimullin, K. R.
Title Countermeasures against blinding attack on superconducting nanowire detectors for QKD Type Conference Article
Year (up) 2015 Publication EPJ Web Conf. Abbreviated Journal EPJ Web Conf.
Volume 103 Issue Pages 10002 (1 to 2)
Keywords SSPD, SNSPD, QKD
Abstract Nowadays, the superconducting single-photon detectors (SSPDs) are used in Quantum Key Distribution (QKD) instead of single-photon avalanche photodiodes. Recently bright-light control of the SSPD has been demonstrated. This attack employed a “backdoor” in the detector biasing technique. We developed the autoreset system which returns the SSPD to superconducting state when it is latched. We investigate latched state of the SSPD and define limit conditions for effective blinding attack. Peculiarity of the blinding attack is a long nonsingle photon response of the SSPD. It is much longer than usual single photon response. Besides, we need follow up response duration of the SSPD. These countermeasures allow us to prevent blind attack on SSPDs for Quantum Key Distribution.
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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 2100-014X ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1352
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Author Rath, P.; Vetter, A.; Kovalyuk, V.; Ferrari, S.; Kahl, O.; Nebel, C.; Goltsman, G. N.; Korneev, A.; Pernice, W. H. P.
Title Travelling-wave single-photon detectors integrated with diamond photonic circuits: operation at visible and telecom wavelengths with a timing jitter down to 23 ps Type Conference Article
Year (up) 2016 Publication Integrated Optics: Devices, Mat. Technol. XX Abbreviated Journal Integrated Optics: Devices, Mat. Technol. XX
Volume 9750 Issue Pages 135-142
Keywords SSPD, Superconducting Nanowire Single-Photon Detector, SNSPD, Single Photon Detector, Diamond Photonics, Diamond Integrated Optics, Diamond Waveguides, Integrated Optics, Low Timing Jitter
Abstract We report on the design, fabrication and measurement of travelling-wave superconducting nanowire single-photon detectors (SNSPDs) integrated with polycrystalline diamond photonic circuits. We analyze their performance both in the near-infrared wavelength regime around 1600 nm and at 765 nm. Near-IR detection is important for compatibility with the telecommunication infrastructure, while operation in the visible wavelength range is relevant for compatibility with the emission line of silicon vacancy centers in diamond which can be used as efficient single-photon sources. Our detectors feature high critical currents (up to 31 μA) and high performance in terms of efficiency (up to 74% at 765 nm), noise-equivalent power (down to 4.4×10-19 W/Hz1/2 at 765 nm) and timing jitter (down to 23 ps).
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Corporate Author Thesis
Publisher Spie Place of Publication Editor Broquin, J.-E.; Conti, G.N.
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 1210
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Author Vetter, A.; Ferrari, S.; Rath, P.; Alaee, R.; Kahl, O.; Kovalyuk, V.; Diewald, S.; Goltsman, G. N.; Korneev, A.; Rockstuhl, C.; Pernice, W. H. P.
Title Cavity-enhanced and ultrafast superconducting single-photon detectors Type Journal Article
Year (up) 2016 Publication Nano Lett. Abbreviated Journal Nano Lett.
Volume 16 Issue 11 Pages 7085-7092
Keywords SSPD; SNSPD; multiphoton detection; nanophotonic circuit; photonic crystal cavity
Abstract Ultrafast single-photon detectors with high efficiency are of utmost importance for many applications in the context of integrated quantum photonic circuits. Detectors based on superconductor nanowires attached to optical waveguides are particularly appealing for this purpose. However, their speed is limited because the required high absorption efficiency necessitates long nanowires deposited on top of the waveguide. This enhances the kinetic inductance and makes the detectors slow. Here, we solve this problem by aligning the nanowire, contrary to usual choice, perpendicular to the waveguide to realize devices with a length below 1 mum. By integrating the nanowire into a photonic crystal cavity, we recover high absorption efficiency, thus enhancing the detection efficiency by more than an order of magnitude. Our cavity enhanced superconducting nanowire detectors are fully embedded in silicon nanophotonic circuits and efficiently detect single photons at telecom wavelengths. The detectors possess subnanosecond decay ( approximately 120 ps) and recovery times ( approximately 510 ps) and thus show potential for GHz count rates at low timing jitter ( approximately 32 ps). The small absorption volume allows efficient threshold multiphoton detection.
Address Institute of Physics, University of Munster , 48149 Munster, Germany
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 1530-6984 ISBN Medium
Area Expedition Conference
Notes PMID:27759401 Approved no
Call Number Serial 1208
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Author Kardakova, A.; Shishkin, A.; Semenov, A.; Goltsman, G. N.; Ryabchun, S.; Klapwijk, T. M.; Bousquet, J.; Eon, D.; Sacépé, B.; Klein, T.; Bustarret, E.
Title Relaxation of the resistive superconducting state in boron-doped diamond films Type Journal Article
Year (up) 2016 Publication Phys. Rev. B Abbreviated Journal Phys. Rev. B
Volume 93 Issue 6 Pages 064506
Keywords boron-doped diamond films, resistive superconducting state, relaxation time
Abstract We report a study of the relaxation time of the restoration of the resistive superconducting state in single crystalline boron-doped diamond using amplitude-modulated absorption of (sub-)THz radiation (AMAR). The films grown on an insulating diamond substrate have a low carrier density of about 2.5×1021cm−3 and a critical temperature of about 2K. By changing the modulation frequency we find a high-frequency rolloff which we associate with the characteristic time of energy relaxation between the electron and the phonon systems or the relaxation time for nonequilibrium superconductivity. Our main result is that the electron-phonon scattering time varies clearly as T−2, over the accessible temperature range of 1.7 to 2.2 K. In addition, we find, upon approaching the critical temperature Tc, evidence for an increasing relaxation time on both sides of Tc.
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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 2469-9950 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1167
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