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Author Huebers, Heinz-Wilhelm; Pavlov, S.; Semenov, A.; Köhler, R.; Mahler, L.; Tredicucci, A.; Beere, H.; Ritchie, D.; Linfield, E.
Title Terahertz quantum cascade laser as local oscillator in a heterodyne receiver Type (up) Journal Article
Year 2005 Publication Optics Express Abbreviated Journal
Volume 13 Issue 15 Pages 5890-5896
Keywords QCL heterodyne, 6 mW at 2.5 THz, HEB mixer, terahertz
Abstract Terahertz quantum cascade lasers have been investigated with respect to their performance as a local oscillator in a heterodyne receiver. The beam profile has been measured and transformed in to a close to Gaussian profile resulting in a good matching between the field patterns of the quantum cascade laser and the antenna of a superconducting hot electron bolometric mixer. Noise temperature measurements with the hot electron bolometer and a 2.5 THz quantum cascade laser yielded the same result as with a gas laser as local oscillator.
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Call Number Serial 627
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Author Rabanus, D.; Graf, U. U.; Philipp, M.; Ricken, O.; Stutzki, J.; Vowinkel, B.; Wiedner, M. C.; Walther, C.; Fischer, M.; Faist, J.
Title Phase locking of a 1.5 terahertz quantum cascade laser and use as a local oscillator in a heterodyne HEB receiver Type (up) Journal Article
Year 2009 Publication Optics Express Abbreviated Journal
Volume 17 Issue 3 Pages 1159-1168
Keywords QCL heterodyne, 300 uW at 1.5 THz, HEB mixer
Abstract We demonstrate for the first time the closure of an electronic phase lock loop for a continuous–wave quantum cascade laser (QCL) at 1.5 THz. The QCL is operated in a closed cycle cryo cooler. We achieved a frequency stability of better than 100 Hz, limited by the resolution bandwidth of the spectrum analyser. The PLL electronics make use of the intermediate frequency (IF) obtained from a hot electron bolometer (HEB) which is downconverted to a PLL IF of 125 MHz. The coarse selection of the longitudinal mode and the fine tuning is achieved via the bias voltage of the QCL. Within a QCL cavity mode, the free-running QCL shows frequency fluctuations of about 5 MHz, which the PLL circuit is able to control via the Stark–shift of the QCL gain material. Temperature dependent tuning is shown to be nonlinear, and of the order of -16 MHz/K. Additionally we have used the QCL as local oscillator (LO) to pump an HEB and perform, again for the first time at 1.5 THz, a heterodyne experiment, and obtain a receiver noise temperature of 1741 K.
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Call Number Serial 628
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Author Ryabchun, Sergey; Tong, Cheuk-Yu Edward; Paine, Scott; Lobanov, Yury; Blundell, Raymond; Goltsman, Gregory
Title Temperature resolution of an HEB receiver at 810 GHz Type (up) Journal Article
Year 2009 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 19 Issue 3 Pages 293-296
Keywords HEB mixer
Abstract We present the results of direct measurements of the temperature resolution of an HEB receiver operating at 810 GHz, in both continuum and spectroscopic modes. In the continuum mode, the input of the receiver was switched between black bodies with different physical temperatures. With a system noise temperature of around 1100 K, the receiver was able to resolve loads which differed in temperature by about 1 K over an integration time of 5 seconds. This resolution is significantly worse than the value of 0.07 K given by the radiometer equation. In the spectroscopic mode, a gas cell filled with carbonyl sulphide (OCS) gas was used and the emission line at 813.3537060 GHz was measured using the receiver in conjunction with a digital spectrometer. From the observed spectra, we determined that the measurement uncertainty of the equivalent emission temperature was 2.8 K for an integration time of 0.25 seconds and a spectral resolution of 12 MHz, compared to a 1.4 K temperature resolution given by the radiometer equation. This relative improvement is due to the fact that at short integration times the contribution from 1/f noise and drift are less dominant. In both modes, the temperature resolution was improved by about 40% with the use of a feedback loop which adjusted the level of an injected microwave radiation to maintain a constant operating current of the HEB mixer. This stabilization scheme has proved to be very effective to keep the temperature resolution of the HEB receiver to close to the theoretical value given by the radiometer equation.
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Call Number Serial 636
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Author Tretyakov, Ivan; Ryabchun, Sergey; Finkel, Matvey; Maslennikova, Anna; Kaurova, Natalia; Lobastova, Anastasia; Voronov, Boris; Gol'tsman, Gregory
Title Low noise and wide bandwidth of NbN hot-electron bolometer mixers Type (up) Journal Article
Year 2011 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.
Volume 98 Issue Pages 033507 (1 to 3)
Keywords NbN HEB mixer
Abstract We report a record double sideband noise temperature of 600 K (5hν/kB) offered by a NbN hot-electron bolometer receiver at 2.5 THz. Allowing for standing wave effects, this value was found to be constant in the intermediate frequency range 1–7 GHz, which indicates that the mixer has an unprecedentedly large noise bandwidth in excess of 7 GHz. The insight into this is provided by gain bandwidth measurements performed at the superconducting transition. They show that the dependence of the bandwidth on the mixer length follows the model for an HEB mixer with diffusion and phonon cooling of the hot electrons.
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Call Number RPLAB @ gujma @ Serial 638
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Author Масленникова, А. В.; Рябчун, С. А.; Финкель, М. И.; Каурова, Н. С.; Исупова, А. А.; Воронов, Б. М.; Гольцман, Г. Н.
Title Широкополосные смесители на горячих электронах на основе NbN наноструктур Type (up) Journal Article
Year 2011 Publication Труды Московского физико-технического института Abbreviated Journal Труды МФТИ
Volume 3 Issue 2 Pages 31-34
Keywords HEB mixer
Abstract Мы приводим данные исследования полосы преобразования смесителей на горячих электронах (hot-electron bolometer, НЕВ), изготовленных на основе тонких пленок NbN. Зависимость полосы преобразования от длины смесительного элемента находится в прекрасном согласии с результатами теоретической модели HEB-смесителя, в котором энергетическая релаксация электронов одновременно происходит по двум каналам: фононному и диффузионному.
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Call Number RPLAB @ gujma @ Serial 646
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Author Tret’yakov, I. V.; Ryabchun, S. A.; Kaurova, N. S.; Larionov, P. A.; Lobastova, A. A.; Voronov, B. M.; Finkel, M. I.; Gol’tsman, G. N.
Title Optimum absorbed heterodyne power for superconducting NbN hot-electron bolometer mixer Type (up) Journal Article
Year 2010 Publication Tech. Phys. Lett. Abbreviated Journal Tech. Phys. Lett.
Volume 36 Issue 12 Pages 1103-1105
Keywords NbN HEB mixer
Abstract Absorbed heterodyne power has been measured in a low-noise broadband hot-electron bolometer (HEB) mixer for the terahertz range, operating on the effect of electron heating in the resistive state of an ultrathin superconducting NbN film. It is established that the optimum absorbed heterodyne power for the HEB mixer operating at 2.5 THz is about 100 nW.
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ISSN 1063-7850 ISBN Medium
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Notes Approved no
Call Number Serial 1389
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Author 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 (up) 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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ISSN 1818-7994 ISBN Medium
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Notes УДК 538.9 Approved no
Call Number RPLAB @ gujma @ Serial 708
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Author Tretyakov, Ivan; Ryabchun, Sergey; Finkel, Matvey; Maslennikov, Sergey; Maslennikova, Anna; Kaurova, Natalia; Lobastova, Anastasia; Voronov, Boris; Gol'tsman, Gregory
Title Ultrawide noise bandwidth of NbN hot-electron bolometer mixers with in situ gold contacts Type (up) Journal Article
Year 2011 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal
Volume 21 Issue 3 Pages 620-623
Keywords NbN HEB mixer bandwidth
Abstract We report a noise bandwidth of 7 GHz in the new generation of NbN hot-electron bolometer (HEB) mixers that are being developed for the space observatory Millimetron. The HEB receiver driven by a 2.5-THz local oscillator offered a noise temperature of 600 K in a 50-MHz final detection bandwidth. As the filter center frequency was swept this value remained nearly constant up to the cutoff frequency of the cryogenic amplifier at 7 GHz. We believe that such a low value of the noise temperature is due to reduced radio frequency (RF) loss at the interface between the superconducting film and the gold contacts. We have also performed gain bandwidth measurements at the superconducting transition on HEB mixers with various lengths and found them to be in excellent agreement with the results of the analytical and numerical models developed for the HEB mixer with both diffusion and phonon cooling of hot electrons.
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Call Number RPLAB @ gujma @ Serial 716
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Author Lobanov, Y.; Tong, E.; Blundell, R.; Hedden, A.; Voronov, B.; Gol'tsman, G.
Title Large-signal frequency response of an HEB mixer: from 300 MHz to terahertz Type (up) Journal Article
Year 2011 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal
Volume 21 Issue 3 Pages 628-631
Keywords waveguide NbN HEB mixers
Abstract We present a study of the large signal frequency response of an HEB mixer over a wide frequency range. In our experiments, we have subjected the HEB mixer to incident electromagnetic radiation from 0.3 GHz to 1 THz. The mixer element is an NbN film deposited on crystalline quartz. The mixer chip is mounted in a waveguide cavity, coupled to free space with a diagonal horn. At microwave frequencies, electromagnetic radiation is applied through the coaxial bias port of the mixer block. At higher frequencies the input signal passes via the diagonal horn feed. At each frequency, the incident power is varied and a family of I-V curves is recorded. From the curves we identify 3 distinct regimes of operation of the mixer separated by the phonon relaxation frequency and the superconducting energy gap frequency observed at about 3 GHz and 660 GHz respectively. In this paper, we will present observed curves and discuss the results of our experiment.
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Call Number RPLAB @ gujma @ Serial 719
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Author Lobanov, Y.V.; Tong, C.-Y.E.; Hedden, A.S.; Blundell, R.; Voronov, B.M.; Gol'tsman, G.N.
Title Direct measurement of the gain and noise bandwidths of HEB mixers Type (up) Journal Article
Year 2011 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 21 Issue 3 Pages 645-648
Keywords waveguide NbN HEB mixers
Abstract The intermediate frequency (IF) bandwidth of a hot electron bolometer (HEB) mixer is an important parameter of the mixer, in that it helps to determine its suitability for a given application. With the availability of wideband low noise amplifiers, it is simple to measure the performance of an HEB mixer over a wide range of IF at a fixed LO frequency using the standard Y-factor method. This in-situ method allows us to measure both the gain and noise bandwidths simultaneously. We have also measured mixer output impedance with a vector network analyser. Intrinsic time constant has been extracted from the impedance data and compared to the mixer's bandwidths determined from receiver Y-factor measurement.
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Call Number RPLAB @ gujma @ Serial 720
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Author Burke, P. J.; Schoelkopf, R. J.; Prober, D. E.; Skalare, A.; Karasik, B. S.; Gaidis, M. C.; McGrath, W. R.; Bumble, B.; Leduc, H. G.
Title Spectrum of thermal fluctuation noise in diffusion and phonon cooled hot-electron mixers Type (up) Journal Article
Year 1998 Publication Applied Physics Letters Abbreviated Journal Appl. Phys. Lett.
Volume 72 Issue 12 Pages 1516-1518
Keywords HEB mixer; thermal fluctuation noise; TFN
Abstract A systematic study of the intermediate frequency noise bandwidth of Nb thin-film superconducting hot-electron bolometers is presented. We have measured the spectrum of the output noise as well as the conversion efficiency over a very broad intermediate frequency range (from 0.1 to 7.5 GHz) for devices varying in length from 0.08 μm to 3 μm. Local oscillator and rf signals from 8 to 40 GHz were used. For a device of a given length, the spectrum of the output noise and the conversion efficiency behave similarly for intermediate frequencies less than the gain bandwidth, in accordance with a simple thermal model for both the mixing and thermal fluctuation noise. For higher intermediate frequencies the conversion efficiency decreases; in contrast, the noise decreases but has a second contribution which dominates at higher frequency. The noise bandwidth is larger than the gain bandwidth, and the mixer noise is low, between 120 and 530 K (double side band).
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Call Number RPLAB @ gujma @ Serial 760
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Author Pütz, P.; Honingh, C. E.; Jacobs, K.; Justen, M.; Schultz, M.; Stutzki, J.
Title Terahertz hot electron bolometer waveguide mixers for GREAT Type (up) Journal Article
Year 2012 Publication Astron. Astrophys. Abbreviated Journal A&A
Volume 542 Issue Pages L2
Keywords HEB mixer, applications
Abstract Context. Supplementing the publications based on the first-light observations with the German REceiver for Astronomy at Terahertz frequencies (GREAT) on SOFIA, we present background information on the underlying heterodyne detector technology. This Letter complements the GREAT instrument Letter and focuses on the mixers itself.

Aims. We describe the superconducting hot electron bolometer (HEB) detectors that are used as frequency mixers in the L1 (1400 GHz), L2 (1900 GHz), and M (2500 GHz) channels of GREAT. Measured performance of the detectors is presented and background information on their operation in GREAT is given.

Methods. Our mixer units are waveguide-based and couple to free-space radiation via a feedhorn antenna. The HEB mixers are designed, fabricated, characterized, and flight-qualified in-house. We are able to use the full intermediate frequency bandwidth of the mixers using silicon-germanium multi-octave cryogenic low-noise amplifiers with very low input return loss.

Results. Superconducting HEB mixers have proven to be practical and sensitive detectors for high-resolution THz frequency spectroscopy on SOFIA. We show that our niobium-titanium-nitride (NbTiN) material HEBs on silicon nitride (SiN) membrane substrates have an intermediate frequency (IF) noise roll-off frequency above 2.8 GHz, which does not limit the current receiver IF bandwidth. Our mixer technology development efforts culminate in the first successful operation of a waveguide-based HEB mixer at 2.5 THz and deployment for radioastronomy. A significant contribution to the success of GREAT is made by technological development, thorough characterization and performance optimization of the mixer and its IF interface for receiver operation on SOFIA. In particular, the development of an optimized mixer IF interface contributes to the low passband ripple and excellent stability, which GREAT demonstrated during its initial successful astronomical observation runs.
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Call Number Serial 907
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Author Cherednichenko, Sergey; Drakinskiy, Vladimir; Berg, Therese; Khosropanah, Pourya; Kollberg, Erik
Title Hot-electron bolometer terahertz mixers for the Herschel Space Observatory Type (up) Journal Article
Year 2008 Publication Review of Scientific Instruments Abbreviated Journal Rev. Sci. Instrum.
Volume 79 Issue Pages 034501
Keywords HEB mixer, HEB detector, HEB direct detector, applications
Abstract We report on low noise terahertz mixers(1.4–1.9THz) developed for the heterodyne spectrometer onboard the Herschel Space Observatory. The mixers employ double slot antenna integrated superconducting hot-electron bolometers (HEBs) made of thin NbN films. The mixer performance was characterized in terms of detection sensitivity across the entire rf band by using a Fourier transform spectrometer (from 0.5to2.5THz, with 30GHz resolution) and also by measuring the mixernoise temperature at a limited number of discrete frequencies. The lowest mixernoise temperature recorded was 750K [double sideband (DSB)] at 1.6THz and 950KDSB at 1.9THz local oscillator (LO) frequencies. Averaged across the intermediate frequency band of 2.4–4.8GHz, the mixernoise temperature was 1100KDSB at 1.6THz and 1450KDSB at 1.9THz LO frequencies. The HEB heterodyne receiver stability has been analyzed and compared to the HEB stability in the direct detection mode. The optimal local oscillator power was determined and found to be in a 200–500nW range.
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Call Number Serial 908
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Author Yagoubov, P.; Kroug, M.; Merkel, H.; Kollberg, E.; Gol'tsman, G.; Svechnikov, S.; Gershenzon, E.
Title Noise temperature and local oscillator power requirement of NbN phonon-cooled hot electron bolometric mixers at terahertz frequencies Type (up) Journal Article
Year 1998 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.
Volume 73 Issue 19 Pages 2814-2816
Keywords NbN HEB mixers, noise temperature, local oscillator power
Abstract In this letter, the noise performance of NbN-based phonon-cooled hot electron bolometric quasioptical mixers is investigated in the 0.55–1.1 THz frequency range. The best results of the double-sideband <cd><2018>DSB<cd><2019> noise temperature are: 500 K at 640 GHz, 600 K at 750 GHz, 850 K at 910 GHz, and 1250 K at 1.1 THz. The water vapor in the signal path causes significant contribution to the measured receiver noise temperature around 1.1 THz. The devices are made from 3-nm-thick NbN film on high-resistivity Si and integrated with a planar spiral antenna on the same substrate. The in-plane dimensions of the bolometer strip are typically 0.2Ï«2 um. The amount of local oscillator power absorbed in the bolometer is less than 100 nW.
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Call Number Serial 911
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Author Phillips, T. G.; Jefferts, K. B.
Title A low temperature bolometer heterodyne receiver for Millimeter wave astronomy Type (up) Journal Article
Year 1973 Publication Rev. Sci. Instrum. Abbreviated Journal Rev. Sci. Instrum.
Volume 44 Issue 8 Pages 1009-1014
Keywords InSb HEB mixer
Abstract Liquid helium cooled InSb hot electronbolometers are used in a balanced mixer configuration as detectors for an imagelessmicrowave receiver. The system is designed for mounting at the prime focus of the National Radio Astronomy Observatory (NRAO) 11 m antenna at Kitt Peak, Arizona, and is suitable for the study of rotational line spectra of interstellar gas molecules. Currently the operating frequency is in the 90–140 GHz band where the double sideband system noise temperature is 250 K.
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Notes Recommended by Klapwijk Approved no
Call Number Serial 927
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