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Author Gol’tsman, G. N.; Okunev, O.; Chulkova, G.; Lipatov, A.; Semenov, A.; Smirnov, K.; Voronov, B.; Dzardanov, A.; Williams, C.; Sobolewski, R.
Title Picosecond superconducting single-photon optical detector Type Journal Article
Year 2001 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.
Volume 79 Issue 6 Pages 705-707
Keywords NbN SSPD, SNSPD
Abstract We experimentally demonstrate a supercurrent-assisted, hotspot-formation mechanism for ultrafast detection and counting of visible and infrared photons. A photon-induced hotspot leads to a temporary formation of a resistive barrier across the superconducting sensor strip and results in an easily measurable voltage pulse. Subsequent hotspot healing in ∼30 ps time frame, restores the superconductivity (zero-voltage state), and the detector is ready to register another photon. Our device consists of an ultrathin, very narrow NbN strip, maintained at 4.2 K and current-biased close to the critical current. It exhibits an experimentally measured quantum efficiency of ∼20% for 0.81 μm wavelength photons and negligible dark counts.
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Series Editor Series Title Abbreviated Series Title
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ISSN 0003-6951 ISBN Medium
Area Expedition Conference
Notes (up) Approved no
Call Number Serial 1543
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Author Xu, Y.; Zheng, X.; Williams, C.; Verevkin, A.; Sobolewski, R.; Chulkova, G.; Lipatov, A.; Okunev, O.; Smirnov, K.; Gol’tsman, G. N.
Title Ultrafast superconducting hot-electron single-photon detector Type Conference Article
Year 2001 Publication CLEO Abbreviated Journal CLEO
Volume Issue Pages 345
Keywords NbN SSPD, SNSPD
Abstract Summary form only given. The current most-pressing need is to develop a practical, GHz-range counting single-photon detector, operational at either 1.3-/spl mu/m or 1.55-/spl mu/m radiation wavelength, for novel quantum communication and quantum cryptography systems. The presented solution of the problem is to use an ultrafast hot-electron photodetector, based on superconducting thin-film microstructures. This type of device is very promising, due to the macroscopic quantum nature of superconductors. Very fast response time and the small, (meV range) value of the superconducting energy gap characterize the superconductor, leading to the efficient avalanche process even for infrared photons.
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Area Expedition Conference Technical Digest. Summaries of papers presented at the Conference on Lasers and Electro-Optics. Postconference Technical Digest (IEEE Cat. No.01CH37170)
Notes (up) Approved no
Call Number Serial 1545
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Author Huebers, H.-W.; Semenov, A.; Schubert, J.; Gol’tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.; Krabbe, A.; Roeser, H.-P.
Title NbN hot-electron bolometer as THz mixer for SOFIA Type Conference Article
Year 2000 Publication Proc. SPIE Abbreviated Journal Proc. SPIE
Volume 4014 Issue Pages 195-202
Keywords NbN HEB mixers, airborne, stratospheric observatory, SOFIA
Abstract Heterodyne receivers for applications in astronomy need quantum limited sensitivity. We have investigated phonon- cooled NbN hot electron bolometric mixers in the frequency range from 0.7 THz to 5.2 THz. The devices were 3.5 nm thin films with an in-plane dimension of 1.7 X 0.2 micrometers 2 integrated in a complementary logarithmic spiral antenna. The best measured DSB receiver noise temperatures are 1300 K (0.7 THz), 2000 K (1.4 THz), 2100 K (1.6 THz), 2600 K (2.5 THz), 4000 K (3.1 THz), 5600 K (4.3 THz), and 8800 K (5.2 THz). The sensitivity fluctuation, the long term stability, and the antenna pattern were measured. The results demonstrate that this mixer is very well suited for GREAT, the German heterodyne receiver for SOFIA.
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Publisher SPIE Place of Publication Editor Melugin, R.K.; Roeser, H.-P.
Language Summary Language Original Title
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ISSN ISBN Medium
Area Expedition Conference Airborne Telescope Systems
Notes (up) Approved no
Call Number Serial 1554
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Author Semenov, A. D.; Gol’tsman, G. N.
Title Nonthermal mixing mechanism in a diffusion-cooled hot-electron detector Type Journal Article
Year 2000 Publication J. Appl. Phys. Abbreviated Journal J. Appl. Phys.
Volume 87 Issue 1 Pages 502-510
Keywords NbN HEB mixers, nonthermal
Abstract We present an analysis of a diffusion-cooled hot-electron detector fabricated from clean superconducting material with low transition temperature. The distinctive feature of a clean material, i.e., material with large electron mean free path, is a relatively weak inelastic electron scattering that is not sufficient for the establishment of an elevated thermodynamic electron temperature when the detector is subjected to irradiation. We propose an athermal model of a diffusion-cooled detector that relies on suppression of the superconducting energy gap by the actual dynamic distribution of excess quasiparticles. The resistive state of the device is caused by the electric field penetrating into the superconducting bridge from metal contacts. The dependence of the penetration length on the energy gap delivers the detection mechanism. The sources of the electric noise are equilibrium fluctuations of the number of thermal quasiparticles and frequency dependent shot noise. Using material parameters typical for A1, we evaluate performance of the device in the heterodyne regime at terahertz frequencies. Estimates show that the mixer may have a noise temperature of a few quantum limits and a bandwidth of a few tens of GHz, while the required local oscillator power is in the μW range due to ineffective suppression of the energy gap by quasiparticles with high energies.
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ISSN 0021-8979 ISBN Medium
Area Expedition Conference
Notes (up) Approved no
Call Number Serial 1558
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Author Gerecht, E.; Musante, C. F.; Zhuang, Y.; Yngvesson, K. S.; Gol’tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.
Title NbN hot electron bolometric mixerss—a new technology for low-noise THz receivers Type Journal Article
Year 1999 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 47 Issue 12 Pages 2519-2527
Keywords NbN HEB mixers
Abstract New advances in hot electron bolometer (HEB) mixers have recently resulted in record-low receiver noise temperatures at terahertz frequencies. We have developed quasi-optically coupled NbN HEB mixers and measured noise temperatures up to 2.24 THz, as described in this paper. We project the anticipated future performance of such receivers to have even lower noise temperature and local-oscillator power requirement as well as wider gain and noise bandwidths. We introduce a proposal for integrated focal plane arrays of HEB mixers that will further increase the detection speed of terahertz systems.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1557-9670 ISBN Medium
Area Expedition Conference
Notes (up) Approved no
Call Number Serial 1560
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