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Milostnaya, I.; Korneev, A.; Rubtsova, I.; Seleznev, V.; Minaeva, O.; Chulkova, G.; Okunev, O.; Voronov, B.; Smirnov, K.; Gol'tsman, G.; Slysz, W.; Wegrzecki, M.; Guziewicz, M.; Bar, J.; Gorska, M.; Pearlman, A.; Kitaygorsky, J.; Cross, A.; Sobolewski, R. | ||||
| Title | Superconducting single-photon detectors designed for operation at 1.55-µm telecommunication wavelength | Type | Conference Article | ||
| Year | 2006 | Publication | J. Phys.: Conf. Ser. | Abbreviated Journal | J. Phys.: Conf. Ser. |
| Volume | 43 | Issue | Pages | 1334-1337 | |
| Keywords | NbN SSPD, SNSPD | ||||
| Abstract | We report on our progress in development of superconducting single-photon detectors (SSPDs), specifically designed for secure high-speed quantum communications. The SSPDs consist of NbN-based meander nanostructures and operate at liquid helium temperatures. In general, our devices are capable of GHz-rate photon counting in a spectral range from visible light to mid-infrared. The device jitter is 18 ps and dark counts can reach negligibly small levels. The quantum efficiency (QE) of our best SSPDs for visible-light photons approaches a saturation level of ~30-40%, which is limited by the NbN film absorption. For the infrared range (1.55µm), QE is ~6% at 4.2 K, but it can be significantly improved by reduction of the operation temperature to the 2-K level, when QE reaches ~20% for 1.55-µm photons. In order to further enhance the SSPD efficiency at the wavelength of 1.55 µm, we have integrated our detectors with optical cavities, aiming to increase the effective interaction of the photon with the superconducting meander and, therefore, increase the QE. A successful effort was made to fabricate an advanced SSPD structure with an optical microcavity optimized for absorption of 1.55 µm photons. The design consisted of a quarter-wave dielectric layer, combined with a metallic mirror. Early tests performed on relatively low-QE devices integrated with microcavities, showed that the QE value at the resonator maximum (1.55-µm wavelength) was of the factor 3-to-4 higher than that for a nonresonant SSPD. Independently, we have successfully coupled our SSPDs to single-mode optical fibers. The completed receivers, inserted into a liquid-helium transport dewar, reached ~1% system QE for 1.55 µm photons. The SSPD receivers that are fiber-coupled and, simultaneously, integrated with resonators are expected to be the ultimate photon counters for optical quantum communications. | ||||
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| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1742-6588 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1450 | |||
| Permanent link to this record | |||||
| Author |
Meledin, D.; Tong, C. Y.-E.; Blundell, R.; Kaurova, N.; Smirnov, K.; Voronov, B.; Gol'tsman, G. | ||||
| Title | The sensitivity and IF bandwidth of waveguide NbN hot electron bolometer mixers on MgO buffer layers over crystalline quartz | Type | Conference Article | ||
| Year | 2002 | Publication | Proc. 13th Int. Symp. Space Terahertz Technol. | Abbreviated Journal | Proc. 13th Int. Symp. Space Terahertz Technol. |
| Volume | Issue | Pages | 65-72 | ||
| Keywords | waveguide NbN HEB mixers | ||||
| Abstract | We have developed and characterized waveguide phonon-cooled NbN Hot Electron Bolometer (FMB) mixers fabricated from a 3-4 nm thick NbN film deposited on a 200nm thick MgO buffer layer over crystalline quartz. Double side band receiver noise temperatures of 900-1050 K at 1.035 THz, and 1300-1400 K at 1.26 THz have been measured at an intermediate frequency of 1.5 GHz. The intermediate frequency bandwidth, measured at 0.8 THz LO frequency, is 3.2 GHz at the optimal bias point for low noise receiver operation. | ||||
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| Publisher | Place of Publication | Cambridge, MA, USA | Editor | Harvard university | |
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| Notes | Approved | no | |||
| Call Number | Serial | 326 | |||
| Permanent link to this record | |||||
| Author |
Meledin, D.; Tong, C. Y.-E.; Blundell, R.; Kaurova, N.; Smirnov, K.; Voronov, B.; Gol'tsman, G. | ||||
| Title | Study of the IF bandwidth of NbN HEB mixers based on crystalline quartz substrate with an MgO buffer layer | Type | Journal Article | ||
| Year | 2003 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
| Volume | 13 | Issue | 2 | Pages | 164-167 |
| Keywords | NbN HEB mixer | ||||
| Abstract | In this paper, we present the results of IF bandwidth measurements on 3-4 nm thick NbN hot electron bolometer waveguide mixers, which have been fabricated on a 200-nm thick MgO buffer layer deposited on a crystalline quartz substrate. The 3-dB IF bandwidth, measured at an LO frequency of 0.81 THz, is 3.7 GHz at the optimal bias point for low noise receiver operation. We have also made measurements of the IF dynamic impedance, which allow us to evaluate the intrinsic electron temperature relaxation time and self-heating parameters at different bias conditions. | ||||
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 341 | |||
| Permanent link to this record | |||||
| Author |
Meledin, D. V.; Marrone, D. P.; Tong, C.-Y. E.; Gibson, H.; Blundell, R.; Paine, S. N.; Papa, D.C.; Smith, M.; Hunter, T. R.; Battat, J.; Voronov, B.; Gol'tsman, G. | ||||
| Title | A 1-THz superconducting hot-electron-bolometer receiver for astronomical observations | Type | Journal Article | ||
| Year | 2004 | Publication | IEEE Trans. Microwave Theory Techn. | Abbreviated Journal | IEEE Trans. Microwave Theory Techn. |
| Volume | 52 | Issue | 10 | Pages | 2338-2343 |
| Keywords | NbN HEB mixer, applications | ||||
| Abstract | In this paper, we describe a superconducting hot-electron-bolometer mixer receiver developed to operate in atmospheric windows between 800-1300 GHz. The receiver uses a waveguide mixer element made of 3-4-nm-thick NbN film deposited over crystalline quartz. This mixer yields double-sideband receiver noise temperatures of 1000 K at around 1.0 THz, and 1600 K at 1.26 THz, at an IF of 3.0 GHz. The receiver was successfully tested in the laboratory using a gas cell as a spectral line test source. It is now in use on the Smithsonian Astrophysical Observatory terahertz test telescope in northern Chile. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0018-9480 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1484 | |||
| Permanent link to this record | |||||
| Author |
Mehdi, I.; Gol'tsman, G.; Putz, P. | ||||
| Title | Introduction to the mini-special-issue on the 25th international symposium on space terahertz technology (ISSTT) | Type | Miscellaneous | ||
| Year | 2015 | Publication | IEEE Trans. THz Sci. Technol. | Abbreviated Journal | IEEE Trans. THz Sci. Technol. |
| Volume | 5 | Issue | 1 | Pages | 14-15 |
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| Abstract | THE 25th International Symposium on Space Terahertz Technology (ISSTT) was held in Moscow, Russia, between April 27–30, 2014. The conference was organized by Moscow State Pedagogical University and the Higher School of Economics (National Research University) and Chaired by Professor Gregory Gol'tsman of Moscow State Pedagogical University. The conference was attended by roughly 150 participants from 15 countries. The technology covered by ISSTT includes detectors, devices, circuits and systems in various areas of THz science and technology. Each year this symposium brings together the global THz space science technology community, and as such, emphasizes the broad international collaboration that is required to execute these large complicated instrument programs that dominate this field. However, talks covering technologies for balloon, aircraft, and ground-based telescopes were also presented. In this special section of IEEE Transactions on Terahertz Science and Technology, we include eight expanded papers from the 25th ISSTT symposium. The papers range from development of SIS mixers to optical adjustment systems for radio telescopes. The 26th ISSTT will be held in Boston, MA, USA, during March 16–18, 2015. Researchers and scientist involved in THz research are invited to attend this symposium (more details are at http://www.cfa.harvard.edu/events/2015/isstt2015/). You can access the full list of papers presented at the ISSTT symposia from the National Radio Astronomy Observatory website: http://www.nrao.edu/meetings/isstt/index.shtml Yours sincerely |
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| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2156-342X | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1353 | |||
| Permanent link to this record | |||||