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Author De Luca, M.; Gupta, H.; Neufeld, D.; Gerin, M.; Teyssier, D.; Drouin, B. J.; Pearson, J. C.; Lis, D. C.; Monje, R.; Phillips, T. G.; Goicoechea, J. R.; Godard, B.; Falgarone, E.; Coutens, A.; Bell, T. A. doi  openurl
  Title Herschel/HIFI discovery of HCL+ in the interstellar medium Type Journal Article
  Year 2012 Publication Astrophys. J. Lett. Abbreviated Journal  
  Volume 751 Issue 2 Pages (up) L37  
  Keywords HEB mixer applications, HIFI, Herschel  
  Abstract The radical ion HCl+, a key intermediate in the chlorine chemistry of the interstellar gas, has been identified for the first time in the interstellar medium with the Herschel Space Observatory's Heterodyne Instrument for the Far-Infrared. The ground-state rotational transition of H35Cl+, 2Π3/2 J = 5/2-3/2, showing Λ-doubling and hyperfine structure, is detected in absorption toward the Galactic star-forming regions W31C (G10.6-0.4) and W49N. The complex interstellar absorption features are modeled by convolving in velocity space the opacity profiles of other molecular tracers toward the same sources with the fine and hyperfine structure of HCl+. This structure is derived from a combined analysis of optical data from the literature and new laboratory measurements of pure rotational transitions, reported in the accompanying Letter by Gupta et al. The models reproduce well the interstellar absorption, and the frequencies inferred from the astronomical observations are in exact agreement with those calculated using spectroscopic constants derived from the laboratory data. The detection of H37Cl+ toward W31C, with a column density consistent with the expected 35Cl/37Cl isotopic ratio, provides additional evidence for the identification. A comparison with the chemically related molecules HCl and H2Cl+ yields an abundance ratio of unity with both species (HCl+ : H2Cl+ : HCl ~ 1). These observations also yield the unexpected result that HCl+ accounts for 3%-5% of the gas-phase chlorine toward W49N and W31C, values several times larger than the maximum fraction (~1%) predicted by chemical models.  
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  Call Number Serial 1092  
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Author Chen, J.; Kang, L.; Jin, B. B.; Xu, W. W.; Wu, P. H.; Zhang, W.; Jiang, L.; Li, N.; Shi, S. C.; Gol'tsman, G. N. url  doi
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  Title Properties of terahertz superconducting hot electron bolometer mixers Type Journal Article
  Year 2008 Publication Int. J. Terahertz Sci. Technol. Abbreviated Journal Int. J. Terahertz Sci. Technol.  
  Volume 1 Issue 1 Pages (up) 37-41  
  Keywords NbN HEB mixers, noise temperature  
  Abstract A quasi-optical superconducting niobium nitride (NbN) hot electron bolometer (HEB) mixer has been fabricated and measured in the terahertz (THz) frequency range of 0.5~2.52 THz. A receiver noise temperature of 2000 K at 2.52 THz has been obtained for the mixer without corrections. Also, the effect of a Parylene C anti-reflection (AR) coating on the silicon (Si) lens has been studied.  
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  Notes Approved no  
  Call Number Serial 1417  
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Author Пентин, И. В.; Смирнов, К. В.; Вахтомин, Ю. Б.; Смирнов, А. В.; Ожегов, Р. В.; Дивочий, А. В.; Гольцман, Г. Н. url  openurl
  Title Быстродействующий терагерцевый приемник и инфракрасный счетчик одиночных фотонов на эффекте разогрева электронов в сверхпроводниковых тонкопленочных наноструктурах Type Journal Article
  Year 2011 Publication Труды МФТИ Abbreviated Journal Труды МФТИ  
  Volume 3 Issue 2 Pages (up) 38-42  
  Keywords SSPD, SNSPD, HEB  
  Abstract Представлены результаты создания приемных систем терагерцевого диапазона (0.3-70 ТГц), обладающих рекордным быстродействием (50 пс) и высокой чувствительностью (до 5x 10^(-14) Вт/Гц^(1/2)), а также однофотонных приемных систем ближнего инфракрасного диапазона с квантовой эффективностью 25 %, уровнем темнового счета 10-1c., максимальной скоростью счета ~ 100 МГц и временным разрешением до 50 пс.  
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  Call Number RPLAB @ gujma @ Serial 707  
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Author Semenov, A. D.; Hübers, H.–W.; Schubert, J.; Gol'tsman, G. N.; Elantiev, A. I.; Voronov, B. M.; Gershenzon, E. M. url  openurl
  Title Frequency dependent noise temperature of the lattice cooled hot-electron terahertz mixer Type Conference Article
  Year 2000 Publication Proc. 11th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 11th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages (up) 39-48  
  Keywords NbN HEB mixers  
  Abstract We present the measurements and the theoretical model on the frequency dependent noise temperature of a lattice cooled hot electron bolometer (HEB) mixer in the terahertz frequency range. The experimentally observed increase of the noise temperature with frequency is a cumulative effect of the non-uniform distribution of the high frequency current in the bolometer and the charge imbalance, which occurs near the edges of the normal domain and contacts with normal metal. In addition, we present experimental results which show that the noise temperature of a HEB mixer can be reduced by about 30% due to a Parylene antireflection coating on the Silicon hyperhemispheric lens.  
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  Notes Approved no  
  Call Number Serial 305  
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Author Tretyakov, I.; Maslennikov, S.; Semenov, A.; Safir, O.; Finkel, M.; Ryabchun, S.; Kaurova, N.; Voronov, B.; Goltsman, G.; Klapwijk, T. M. url  openurl
  Title Impact of operating conditions on noise and gain bandwidth of NbN HEB mixers Type Conference Article
  Year 2015 Publication Proc. 26th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 26th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages (up) 39  
  Keywords NbN HEB mixers  
  Abstract Hot-electron bolometer mixers (HEB’s) are the most promising devices as mixing element for terahertz spectroscopy and astronomy at frequencies beyond 1.4 THz. They have a low noise temperature and low demands on local oscillator (LO) power. 1,2 An important limitation is the IF bandwidth, of the order of a few GHz, and which in principle depends on energy relaxation due to electron- phonon processes and on diffusion-cooling. It has been proposed by Prober that a reduction in length of the HEB would lead to an increased bandwidth. 3 This appeared to be achieved by Tretyakov et al by measuring the gain bandwidth close to the critical temperature of the NbN. 2 Unfortunately, the noise bandwidth of similar devices operated at temperatures around 4.2 K appear not depend on the length. The fundamental problem to be addressed is the position-dependent superconducting state of the HEB- devices under operating conditions, which determines the conditions for the cooling of the hot quasiparticles. Some progress has been made by Barends et al in a semi-empirical model to describe the I,V curves under operating conditions at a bath temperature around 4.2 K. 4 In more recent work Vercruyssen et al have analyzed the I,V curve, without any LO-equivalent bias, of a model NSN system. 5 This work suggests that the most appropriate model for an HEB under operating conditions is that of a potential-well in the superconducting gap in the center of the NbN, analogous the bimodal superconducting state described by Vercruyssen et al. Hot quasiparticles in the well can not diffuse out and can only cool by electron-phonon processes, those with higher energies than the heights of the walls of the well can diffuse out. Using this working hypothesis we have carried out experiments on a sub-micrometer NbN bridge connected to a gold (Au) planar spiral antenna. An in situ process is used to deposit Au on NbN. The Au is removed in the center to define the uncovered NbN, which will act as the superconducting mixer itself. The antenna is deposited on the remaining Au layer on the NbN. The Au contacts suppress the energy gap of the NbN film located underneath the gold layer 7,8 . The measured resistive transition is shown in Fig.1. It clearly shows a T c of the bilayer at 6.2 K and the resistive transition of the NbN itself around 9 K. In addition we show the measured noise bandwidth (red squares) for different bath temperatures. Clearly the noise bandwidth increases strongly by increasing the bath temperature from 5 K to 8 K, up to 13 GHz. We interpret this pattern as evidence for improved out-diffusion of hot electrons due to normal banks and a shallow superconducting potential well compared to k B T. As expected the noise temperature in this regime is much bigger than when biased at 4.2 K. R EFERENCES 1 W. Zhang, P. Khosropanah, J. R. Gao, E. L. Kollberg, K. S. Yngvesson, T. Bansal, R. Barends, and T. M. Klapwijk Appl. Phys. Lett. 96, 111113, (2010). 2 Ivan Tretyakov, Sergey Ryabchun, Matvey Finkel, Anna Maslennikova, Natalia Kaurova, Anastasia Lobastova, Boris Voronov, and Gregory Gol’tsman Appl. Phys. Lett. 98, 033507 (2011). 3 D. E. Prober, Appl. Phys. Lett. 62, 2119 (1992). 4 R. Barends, M. Hajenius, J. R. Gao, and T. M. Klapwijk, Appl. Phys. Lett. 87, 263506 (2005). 5 N. Vercruyssen, T. G. A. Verhagen, M. G. Flokstra, J. P. Pekola, and T. M. Klapwijk Physical Review B 85, 224503 (2012).  
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  Call Number Serial 1159  
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Author Trifonov, Andrey; Tong, C. Edward; Lobanov, Yury; Kaurova, Natalia; Blundell, Raymond; Gol’tsman, Gregory url  openurl
  Title An investigation of the DC and IF performance of silicon-membrane HEB mixer elements Type Conference Article
  Year 2015 Publication Proc. 26th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 26th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages (up) 40  
  Keywords silicon-membrane HEB waveguide mixer  
  Abstract We report on our initial development towards a 2x2 multi-pixel HEB waveguide mixer for operation at 1.4 THz. We have successfully fabricated devices comprising an NbN bridge integrated with antenna test structure using a silicon membrane as the supporting substrate. DC measurements of the test chips demonstrate critical current from 0.1 – 1mA depending on the size of device, with T c of around 10 K and ΔTc ~ 0.8 K.  
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  Call Number Serial 1160  
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Author Hübers, H.-W.; Schubert, J.; Krabbe, A.; Birk, M.; Wagner, G.; Semenov, A.; Gol’tsman, G.; Voronov, B.; Gershenzon, E. url  doi
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  Title Parylene anti-reflection coating of a quasi-optical hot-electron-bolometric mixer at terahertz frequencies Type Journal Article
  Year 2001 Publication Infrared Physics & Technology Abbreviated Journal Infrared Physics & Technology  
  Volume 42 Issue 1 Pages (up) 41-47  
  Keywords NbN HEB mixers, anti-reflection coating  
  Abstract Parylene C was investigated as anti-reflection coating for silicon at terahertz frequencies. Measurements with a Fourier-transform spectrometer show that the transmittance of pure silicon can be improved by about 30% when applying a layer of Parylene C with a quarter wavelength optical thickness. The 10% bandwidth of this coating extends from 1.5 to 3 THz for a center frequency of 2.3–2.5 THz, where the transmittance is constant. Heterodyne measurements demonstrate that the noise temperature of a hot-electron-bolometric mixer can be reduced significantly by coating the silicon lens of the hybrid antenna with a quarter wavelength Parylene C layer. Compared to the same mixer with an uncoated lens the improvement is about 30% at a frequency of 2.5 THz.  
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  ISSN 1350-4495 ISBN Medium  
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  Notes Approved no  
  Call Number Serial 1548  
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Author Cherednichenko, S.; Drakinskiy, V.; Lecomte, B.; Dauplay, F.; Krieg, J.-M.; Delorme, Y.; Feret, A.; Hübers, H.-W.; Semenov, A.D.; Gol’tsman, G.N. url  openurl
  Title Terahertz heterodyne array based on NbN HEB mixers Type Abstract
  Year 2008 Publication Proc. 19th Int. Symp. Space Terahertz Technol. Abbreviated Journal  
  Volume Issue Pages (up) 43  
  Keywords NbN HEB mixers array  
  Abstract A 16 pixel heterodyne receiver for 2.5 THz is been developed based on NbN superconducting hot-electron bolometer (HEB) mixers. The receiver uses a quasioptical RF coupling approach where HEB mixers are integrated into double dipole antennas on 1.5μm thick Si3N4 / SiO2 membranes. Miniature mirrors (one per pixel) and back short for the antenna were used to design the output mixer beam profile. The camera design allows all 16 pixel IF readout in parallel. The gain bandwidth of the HEB mixers on Si3N4 / SiO 2 membranes was found to be about 3 GHz, when an MgO buffer layers is applied on the membrane. We will also present the progress in the camera heterodyne tests.  
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  Notes Approved no  
  Call Number Serial 1411  
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Author Smirnov, A. V.; Larionov, P. A.; Finkel, M. I.; Maslennikov, S. N.; Voronov, B. M.; Gol'tsman, G. N. url  openurl
  Title NbZr films for THz phonon-cooled HEB mixers Type Conference Article
  Year 2008 Publication Proc. 19th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 19th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages (up) 44-47  
  Keywords HEB, NbZr, material search  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Groningen, Netherlands Editor  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 577  
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Author Bruderer, S.; Benz, A. O.; van Dishoeck, E. F.; Melchior, M.; Doty, S. D.; van der Tak, F.; Stäuber, P.; Wampfler, S. F.; Dedes, C.; Yıldız, U. A.; Pagani, L.; Giannini, T.; de Graauw, Th.; Whyborn, N.; Teyssier, D.; Jellema, W.; Shipman, R.; Schieder, R.; Honingh, N.; Caux, E.; Bächtold, W.; Csillaghy, A.; Monstein, C.; Bachiller, R.; Baudry, A.; Benedettini, M.; Bergin, E.; Bjerkeli, P.; Blake, G. A.; Bontemps, S.; Braine, J.; Caselli, P.; Cernicharo, J.; Codella, C.; Daniel, F.; di Giorgio, A. M.; Dominik, C.; Encrenaz, P.; Fich, M.; Fuente, A.; Goicoechea, J. R.; Helmich, F.; Herczeg, G. J.; Herpin, F.; Hogerheijde, M. R.; Jacq, T.; Johnstone, D.; Jørgensen, J. K.; Kristensen, L. E.; Larsson, B.; Lis, D.; Liseau, R.; Marseille, M.; McCoey, C.; Melnick, G.; Neufeld, D.; Nisini, B.; Olberg, M.; Parise, B.; Pearson, J. C.; Plume, R.; Risacher, C.; Santiago-García, J.; Saraceno, P.; Shipman, R.; Tafalla, M.; van Kempen, T. A.; Visser, R.; Wyrowski, F. doi  openurl
  Title Herschel/HIFI detections of hydrides towards AFGL 2591. Envelope emission versus tenuous cloud absorption Type Journal Article
  Year 2010 Publication Astron. Astrophys. Abbreviated Journal  
  Volume 521 Issue Pages (up) L44 (1 to 7)  
  Keywords HEB mixer applications, HIFI, Herschel  
  Abstract The Heterodyne Instrument for the Far Infrared (HIFI) onboard the Herschel Space Observatory allows the first observations of light diatomic molecules at high spectral resolution and in multiple transitions. Here, we report deep integrations using HIFI in different lines of hydrides towards the high-mass star forming region AFGL 2591. Detected are CH, CH+, NH, OH+, H2O+, while NH+ and SH+ have not been detected. All molecules except for CH and CH+ are seen in absorption with low excitation temperatures and at velocities different from the systemic velocity of the protostellar envelope. Surprisingly, the CH(JF,P = 3/22,- – 1/21,+ ) and CH+(J = 1–0, J = 2–1) lines are detected in emission at the systemic velocity. We can assign the absorption features to a foreground cloud and an outflow lobe, while the CH and CH+ emission stems from the envelope. The observed abundance and excitation of CH and CH+ can be explained in the scenario of FUV irradiated outflow walls, where a cavity etched out by the outflow allows protostellar FUV photons to irradiate and heat the envelope at larger distances driving the chemical reactions that produce these molecules.  
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  Call Number Serial 1083  
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Author Svechnikov, S.; Verevkin, A.; Voronov, B.; Menschikov, E.; Gershenzon, E.; Gol'tsman, G. url  openurl
  Title Quasioptical phonon-cooled NbN hot electron bolometer mixers at 0.5-1.1 THz Type Conference Article
  Year 1998 Publication Proc. 9th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 9th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages (up) 45-51  
  Keywords NbN HEB mixers  
  Abstract The noise performance of a receiver incorporating spiral antenna coupled NbN phonon-cooled superconducting hot electron bolometric mixer is measured from 450 GHz to 1200 GHz. The mixer element is thin (thickness nm) NbN 1.5 pm wide and 0.2 i.um long film fabricated by lift-off e-beam lithography on high-resistive silicon substrate. The noise of the receiver temperature is 1000 K at 800-900 GHz, 1200 K at 950 GHz, and 1600 K at 1.08 THz. The required (absorbed) local-oscillator power is —20 nW.  
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  Notes Approved no  
  Call Number Serial 1586  
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Author Gerecht, E.; Musante, C. F.; Yngvesson, K. S.; Waldman, J.; Gol'tsman, G. N.; Yagoubov, P. A.; Voronov, B. M.; Gershenzon, E. M. url  openurl
  Title Optical coupling and conversion gain for NbN HEB mixer at THz frequencies Type Conference Article
  Year 1997 Publication Proc. 4-th Int. Semicond. Device Research Symp. Abbreviated Journal Proc. 4-th Int. Semicond. Device Research Symp.  
  Volume Issue Pages (up) 47-50  
  Keywords NbN HEB mixers  
  Abstract  
  Address Charlottesville, Virginia  
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  Notes Approved no  
  Call Number Serial 1601  
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Author Tong, C.-Y. Edward; Kawamura, Jonathan; Todd, R. Hunter; Papa, D. Cosmo; Blundell, Raymond.; Smith, Michael; Patt, Ferdinand; Gol'tsman, Gregory; Gershenzon, Eugene url  openurl
  Title Successful operation of a 1 THz NbN hot-electron bolometer receiver Type Conference Article
  Year 2000 Publication Proc. 11th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 11th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages (up) 49-59  
  Keywords NbN HEB mixers, applications  
  Abstract A phonon-cooled NbN superconductive hot-electron bolometer receiver covering the frequency range 0.8-1.04 THz has successfully been used for astronomical observation at the Sub-Millimeter Telescope Observatory on Mount Graham, Arizona. This waveguide heterodyne receiver is a modified version of our fixed-tuned 800 GHz HEB receiver to allow for operation beyond 1 THz. The measured noise temperature of this receiver is about 1250 K at 0.81 THz, 560 K at 0.84 THz, and 1600 K at 1.035 THz. It has a 1 GHz wide IF bandwidth, centered at 1.8 GHz. This receiver has recently been used to detect the CO (9-8) molecular line emission at 1.037 THz in the Orion nebula. This is the first time a ground-based heterodyne receiver has been used to detect a celestial source above 1 THz.  
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  Notes Approved no  
  Call Number Serial 303  
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Author Hartogh, P.; Jarchow, C.; Lellouch, E.; de Val-Borro, M.; Rengel, M.; Moreno, R.; Medvedev, A. S.; Sagawa, H.; Swinyard, B. M.; Cavalié, T.; Lis, D. C.; BłÄ™cka, M. I.; Banaszkiewicz, M.; Bockelée-Morvan, D.; Crovisier, J.; Encrenaz, T.; Küppers, M.; Lara, L.-M.; Szutowicz, S.; Vandenbussche, B.; Bensch, F.; Bergin, E. A.; Billebaud, F.; Biver, N.; Blake, G. A.; Blommaert, J. A. D. L.; Cernicharo, J.; Decin, L.; Encrenaz, P.; Feuchtgruber, H.; Fulton, T.; de Graauw, T.; Jehin, E.; Kidger, M.; Lorente, R.; Naylor, D. A.; Portyankina, G.; Sánchez-Portal, M.; Schieder, R.; Sidher, S.; Thomas, N.; Verdugo, E.; Waelkens, C.; Whyborn, N.; Teyssier, D.; Helmich, F.; Roelfsema, P.; Stutzki, J.; LeDuc, H. G.; Stern, J. A. doi  openurl
  Title Herschel/HIFI observations of Mars: First detection of O2 at submillimetre wavelengths and upper limits on HCl and H2O2 Type Journal Article
  Year 2010 Publication Astron. Astrophys. Abbreviated Journal  
  Volume 521 Issue Pages (up) L49  
  Keywords HEB mixer applications, HIFI, Herschel, planets and satellites: atmospheres / radiative transfer / submillimeter: general / molecular processes  
  Abstract We report on an initial analysis of Herschel/HIFI observations of hydrogen chloride (HCl), hydrogen peroxide (H2O2), and molecular oxygen (O2) in the Martian atmosphere performed on 13 and 16 April 2010 (Ls ~ 77°). We derived a constant volume mixing ratio of 1400 ± 120 ppm for O2 and determined upper limits of 200 ppt for HCl and 2 ppb for H2O2. Radiative transfer model calculations indicate that the vertical profile of O2 may not be constant. Photochemical models determine the lowest values of H2O2 to be around Ls ~ 75° but overestimate the volume mixing ratio compared to our measurements.  
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  Call Number Serial 1093  
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Author Maret, S.; Bacmann, A.; Bottinelli, S.; Parise, B.; Caux, E.; Faure, A.; Bergin, E. A.; Blake, G. A.; Castets, A.; Ceccarelli, C.; Cernicharo, J.; Coutens, A.; Crimier, N.; Demyk, K.; Dominik, C.; Gerin, M.; Hennebelle, P.; Henning, T.; Kahane, C.; Klotz, A.; Melnick, G.; Pagani, L.; Schilke, P.; Vastel, C.; Wakelam, V.; Walters, A.; Baudry, A.; Bell, T.; Benedettini, M.; Boogert, A.; Cabrit, S.; Caselli, P.; Codella, C.; Comito, C.; Encrenaz, P.; Falgarone, E.; Fuente, A.; Goldsmith, P. F.; Helmich, F.; Herbst, E.; Jacq, T.; Kama, M.; Langer, W.; Lefloch, B.; Lis, D.; Lord, S.; Lorenzani, A.; Neufeld, D.; Nisini, B.; Pacheco, S.; Phillips, T.; Salez, M.; Saraceno, P.; Schuster, K.; Tielens, X.; van der Tak, F.; van der Wiel, M. H. D.; Viti, S.; Wyrowski, F.; Yorke, H. doi  openurl
  Title Nitrogen hydrides in the cold envelope of IRAS 16293-2422 Type Journal Article
  Year 2010 Publication Astron. Astrophys. Abbreviated Journal  
  Volume 521 Issue Pages (up) L52  
  Keywords HEB mixer applications, HIFI, Herschel, ISM: abundances / ISM: general / astrochemistry  
  Abstract Nitrogen is the fifth most abundant element in the Universe, yet the gas-phase chemistry of N-bearing species remains poorly understood. Nitrogen hydrides are key molecules of nitrogen chemistry. Their abundance ratios place strong constraints on the production pathways and reaction rates of nitrogen-bearing molecules. We observed the class 0 protostar IRAS 16293-2422 with the heterodyne instrument HIFI, covering most of the frequency range from 0.48 to 1.78 THz at high spectral resolution. The hyperfine structure of the amidogen radical o-NH2 is resolved and seen in absorption against the continuum of the protostar. Several transitions of ammonia from 1.2 to 1.8 THz are also seen in absorption. These lines trace the low-density envelope of the protostar. Column densities and abundances are estimated for each hydride. We find that NH:NH2:NH3 â‰<2c6> 5:1:300. Dark clouds chemical models predict steady-state abundances of NH2 and NH3 in reasonable agreement with the present observations, whilst that of NH is underpredicted by more than one order of magnitude, even using updated kinetic rates. Additional modelling of the nitrogen gas-phase chemistry in dark-cloud conditions is necessary before having recourse to heterogen processes.  
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  Notes Approved no  
  Call Number Serial 1094  
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