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Author (up) Kooi, J. W.; Baselmans, J. J. A.; Baryshev, A.; Schieder, R.; Hajenius, M.; Gao, J.R.; Klapwijk, T. M.; Voronov, B.; Gol’tsman, G.
Title Stability of heterodyne terahertz receivers Type Journal Article
Year 2006 Publication J. Appl. Phys. Abbreviated Journal J. Appl. Phys.
Volume 100 Issue 6 Pages 064904 (1 to 9)
Keywords NbN HEB mixers
Abstract In this paper we discuss the stability of heterodyne terahertz receivers based on small volume NbN phonon cooled hot electron bolometers (HEBs). The stability of these receivers can be broken down in two parts: the intrinsic stability of the HEB mixer and the stability of the local oscillator (LO) signal injection scheme. Measurements show that the HEB mixer stability is limited by gain fluctuations with a 1∕f spectral distribution. In a 60MHz noise bandwidth this results in an Allan variance stability time of ∼0.3s. Measurement of the spectroscopic Allan variance between two intermediate frequency (IF) channels results in a much longer Allan variance stability time, i.e., 3s between a 2.5 and a 4.7GHz channel, and even longer for more closely spaced channels. This implies that the HEB mixer 1∕f noise is strongly correlated across the IF band and that the correlation gets stronger the closer the IF channels are spaced. In the second part of the paper we discuss atmospheric and mechanical system stability requirements on the LO-mixer cavity path length. We calculate the mixer output noise fluctuations as a result of small perturbations of the LO-mixer standing wave, and find very stringent mechanical and atmospheric tolerance requirements for receivers operating at terahertz frequencies.
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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 0021-8979 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1444
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Author (up) Kooi, Jacob Willem
Title Advanced receivers for submillimeter and far infrared astronomy Type Book Whole
Year 2008 Publication University of Groningen Abbreviated Journal RUG
Volume Issue Pages
Keywords HEB, SIS, TES, NEP, noise temperature, IF bandwidth, waveguide, impedance, conversion gain, FTS, integrated array, stability, Allan variance, multi-layer antireflection coating
Abstract
Address
Corporate Author Thesis Doctoral 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 978-90-367-3653-4 Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 881
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Author (up) Korneev, A.; Finkel, M.; Maslennikov, S.; Korneeva, Yu.; Florya, I.; Tarkhov, M.; Elezov, M.; Ryabchun, S.; Tretyakov, I.; Isupova, A.; Voronov, B.; Goltsman, G.
Title Superconducting NbN terahertz detectors and infrared photon counters Type Journal Article
Year 2010 Publication Вестник НГУ. Серия: физ. Abbreviated Journal Вестник НГУ. Серия: физ.
Volume 5 Issue 4 Pages 68-72
Keywords HEB; HEB mixer
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. Keywords: Hot electron bolometer mixers, infrared single-photon detectors, superconducting device fabrication, superconducting NbN films.
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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 1818-7994 ISBN Medium
Area Expedition Conference
Notes УДК 538.9 Approved no
Call Number RPLAB @ gujma @ Serial 708
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Author (up) Krause, S.; Mityashkin, V.; Antipov, S.; Gol'tsman, G.; Meledin, D.; Desmaris, V.; Belitsky, V.; Rudzinski, M.
Title Study of IF bandwidth of NbN hot electron bolometers on GaN buffer layer using a direct measurement method Type Conference Article
Year 2016 Publication Proc. 27th Int. Symp. Space Terahertz Technol. Abbreviated Journal
Volume Issue Pages 30-32
Keywords NbN HEB, GaN buffer layer
Abstract In this paper, we present a reliable measurement method to study the influence of the GaN buffer layer on phonon-escape time in comparison with commonly used Si substrates and, in consequence, on the IF bandwidth of HEBs. One of the key aspects is to operate the HEB mixer at elevated bath temperatures close to the critical temperature of the NbN ultra-thin film, where contributions from electron-phonon processes and self-heating effects are relatively small, therefore IF roll-off will be governed by the phonon-escape.Two independent experiments were performed at GARD and MSPU on a similar experimental setup at frequencies of approximately 180 and 140 GHz, respectively, and have shown reproducible and consistent results. The entire IF chain was characterized by S-parameter measurements. We compared the measurement results of epitaxial NbN grown onto GaN buffer-layer with Tc of 12.5 K (4.5nm) with high quality polycrystalline NbN films on Si substrate with Tc of 10.5K (5nm) and observed a strong indication of an enhancement of phonon escape to the substrate by a factor of two for the NbN/GaN material combination.
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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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1202
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Author (up) Krause, S.; Mityashkin, V.; Antipov, S.; Gol’tsman, G.; Meledin, D.; Desmaris, V.; Belitsky, V.; Rudziński, M.
Title Reduction of phonon escape time for nbn hot electron bolometers by using gan buffer layers Type Journal Article
Year 2017 Publication IEEE Trans. Terahertz Sci. Technol. Abbreviated Journal IEEE Trans. Terahertz Sci. Technol.
Volume 7 Issue 1 Pages 53-59
Keywords NbN HEB mixer
Abstract In this paper, we investigated the influence of the GaN buffer layer on the phonon escape time of phonon-cooled hot electron bolometers (HEBs) based on NbN material and compared our findings to conventionally employed Si substrate. The presented experimental setup and operation of the HEB close to the critical temperature of the NbN film allowed for the extraction of phonon escape time in a simplified manner. Two independent experiments were performed at GARD/Chalmers and MSPU on a similar experimental setup at frequencies of approximately 180 and 140 GHz, respectively, and have shown reproducible and consistent results. By fitting the normalized IF measurement data to the heat balance equations, the escape time as a fitting parameter has been deduced and amounts to 45 ps for the HEB based on Si substrate as in contrast to a significantly reduced escape time of 18 ps for the HEB utilizing the GaN buffer layer under the assumption that no additional electron diffusion has taken place. This study indicates a high phonon transmissivity of the NbN-to-GaN interface and a prospective increase of IF bandwidth for HEB made of NbN on GaN buffer layers, which is desirable for future THz HEB heterodyne receivers.
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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 2156-3446 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1330
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