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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 | 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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| Notes | Approved | no | |||
| 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 | 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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| Notes | Approved | no | |||
| Call Number | Serial | 908 | |||
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| Author | Leisawitz, David T.; Danchi, William C.; Dipirro, Michael J.; Feinberg, Lee D.; Gezari, Daniel Y.; Hagopian, Mike; Langer, William D.; Mather, John C.; Moseley, Jr. Samuel H.; Shao, Michael; Silverberg, Robert F.; Staguhn, Johannes G.; Swain, Mark R.; Yorke, Harold W.; Zhang, Xiaolei | ||||
| Title | Scientific motivation and technology requirements for the SPIRIT and SPECS far-infrared/submillimeter space interferometers | Type | Conference Article | ||
| Year | 2000 | Publication | Proc. SPIE | Abbreviated Journal | Proc. SPIE |
| Volume | 4013 | Issue | Pages | 36-46 | |
| Keywords | HEB applications | ||||
| Abstract | Far infrared interferometers in space would enable extraordinary measurements of the early universe, the formation of galaxies, stars, and planets, and would have great discovery potential. Since half the luminosity of the universe and 98% of the photons released since the Big Bang are now observable at far IR wavelengths (40 – 500 micrometers ), and the Earth's atmosphere prevents sensitive observations from the ground, this is one of the last unexplored frontiers of space astronomy. We present the engineering and technology requirements that stem from a set of compelling scientific goals and discuss possible configurations for two proposed NASA missions, the Space Infrared Interferometric Telescope and the Submillimeter Probe of the Evolution of Cosmic Structure. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 909 | |||
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| Author | Khosropanah, Pourya | ||||
| Title | NbN and NbTiN hot electron bolometer THz mixers | Type | Book Whole | ||
| Year | 2003 | Publication | Chalmers University of Technology | Abbreviated Journal | |
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| Keywords | HEB mixer, hot electron bolometer mixer, NbN, NbTiN, superconducting detector, heterodyne receiver, THz mixer, submillimeter mixer, quasioptical receiver, double slot antenna, twin slot antenna, spiral antenna, receiver noise, FTS, Fourier Transform Spectrometer | ||||
| Abstract | The thesis reports the development of Hot Electron Bolometer (HEB) mixers for radio astronomy heterodyne receivers in THz frequency range. Part of this work is the fabrication of HEB devices, which are based on NbN or NbTiN superconducting thin films (â‰<a4>5 nm). They are integrated with wideband spiral or double-slot planar antennas. The mixer chips are incorporated into a quasi-optical receiver. The experimental part of this work focuses on the characterization of the receiver as a whole, and the HEB mixers as a part. Double side band receiver noise temperature and the IF bandwidth are reported for frequencies from 0.7 THz up to 2.6 THz. The spectrum of the direct response of HEB integrated with dierent antennas are measured using Fourier Transform Spectrometer (FTS). The effect of the bolometer size on total receiver performance and the LO power requirements is also discussed. A high-yield and reliable process for fabrication of NbN HEB mixers have been achieved. Over 100 devices with different bolometer geometry, film property and also different antennas have been fabricated and measured. The measured data enables us to discuss the impact of different parameters to the receiver overall performance. This work has provided NbN HEB mixers to the following receivers: TREND (Terahertz REceiver with NbN HEB Device) operating at 1.25-1.5 THz, installed in AST/RO Submillimeter Wave Telescope, Amundsen/Scott South Pole Station, in 2002-2003. Band 6-low (1.410-1.700 THz) and 6-high (1.700-1.920 THz) of the HIFI (Heterodyne Instrument for Far Infra-red) in the Herschel Space Observatory, due to launch in 2007 by ESA (European Space Agency). Besides, there has been continuous efforts to develop better models to explain the mixer performance more accurately. They are based on two temperature model for electrons and phonons and solving one-dimensional heat balance equations along the bolometer. The principles of these models are illustrated and the calculated results are compared with measured data. |
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| Corporate Author | Thesis | Ph.D. thesis | |||
| Publisher | Chalmers University of Technology | Place of Publication | Göteborg | Editor | |
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| Notes | Approved | no | |||
| Call Number | Serial | 910 | |||
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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 | 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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| Notes | Approved | no | |||
| Call Number | Serial | 911 | |||
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| Author | Klapwijk, T. M.; Barends, R.; Gao, J. R.; Hajenius, M.; Baselmans, J. J. A. | ||||
| Title | Improved superconducting hot-electron bolometer devices for the THz range | Type | Conference Article | ||
| Year | 2004 | Publication | Proc. SPIE | Abbreviated Journal | Proc. SPIE |
| Volume | 5498 | Issue | Pages | 129-139 | |
| Keywords | HEB mixer distributed model, numerical model | ||||
| Abstract | Improved and reproducible heterodyne mixing (noise temperatures of 950 K at 2.5 THz) has been realized with NbN based hot-electron superconducting devices with low contact resistances. A distributed temperature numerical model of the NbN bridge, based on a local electron and a phonon temperature, has been used to understand the physical conditions during the mixing process. We find that the mixing is predominantly due to the exponential rise of the local resistivity as a function of electron temperature. | ||||
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| Notes | Invited talk, Recommended by Klapwijk | Approved | no | ||
| Call Number | Serial | 912 | |||
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| Author | Gurevich, A. Vl.; Mints, R. G. | ||||
| Title | Self-heating in normal metals and superconductors | Type | Journal Article | ||
| Year | 1987 | Publication | Rev. Mod. Phys. | Abbreviated Journal | |
| Volume | 59 | Issue | 4 | Pages | 941-1000 |
| Keywords | HEB, Joule self-heating effect | ||||
| Abstract | This review is devoted to the physics of current-carrying superconductors and normal metals having two or more stable states sustained by Joule self-heating. The creation, propagation, and localization of electrothermal domains and switching waves leading to the transition from one stable state to another in uniform and nonuniform samples are treated in detail. The connection between thermal bistability and hysteresis, dropping and stepped current-voltage characteristics, self-induced oscillations of current and voltage, selfreplication of electrothermal domains, and the formation of periodic and stochastic resistive structures are considered. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 917 | |||
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| Author | Pekker, David; Shah, Nayana; Sahu, Mitrabhanu; Bezryadin, Alexey; Goldbart, Paul M. | ||||
| Title | Stochastic dynamics of phase-slip trains and superconductive-resistive switching in current-biased nanowires | Type | Journal Article | ||
| Year | 2009 | Publication | Phys. Rev. B | Abbreviated Journal | |
| Volume | 80 | Issue | Pages | 214525 (1 to 17) | |
| Keywords | superconducting nanowire, phase-slip, order parameter, HEB distributed model, HEB model | ||||
| Abstract | Superconducting nanowires fabricated via carbon-nanotube templating can be used to realize and study quasi-one-dimensional superconductors. However, measurement of the linear resistance of these nanowires have been inconclusive in determining the low-temperature behavior of phase-slip fluctuations, both quantal and thermal. Thus, we are motivated to study the nonlinear current-voltage characteristics in current-biased nanowires and the stochastic dynamics of superconductive-resistive switching, as a way of probing phase-slip events. In particular, we address the question: can a single phase-slip event occurring somewhere along the wire—during which the order-parameter fluctuates to zero—induce switching, via the local heating it causes? We explore this and related issues by constructing a stochastic model for the time evolution of the temperature in a nanowire whose ends are maintained at a fixed temperature. We derive the corresponding master equation as a tool for evaluating and analyzing the mean switching time at a given value of current (smaller than the depairing critical current). The model indicates that although, in general, several phase-slip events are necessary to induce switching via a thermal runaway, there is indeed a regime of temperatures and currents in which a single event is sufficient. We carry out a detailed comparison of the results of the model with experimental measurements of the distribution of switching currents, and provide an explanation for the rather counterintuitive broadening of the distribution width that is observed upon lowering the temperature. Moreover, we identify a regime in which the experiments are probing individual phase-slip events, and thus offer a way of unearthing and exploring the physics of nanoscale quantum tunneling of the one-dimensional collective quantum field associated with the superconducting order parameter. | ||||
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| Notes | Recommended by Klapwijk | Approved | no | ||
| Call Number | Serial | 923 | |||
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| Author | Phillips, T. G.; Jefferts, K. B. | ||||
| Title | A low temperature bolometer heterodyne receiver for Millimeter wave astronomy | Type | 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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| Author | Miao, W.; Zhang, W.; Zhong, J. Q.; Shi, S. C.; Delorme, Y.; Lefevre, R.; Feret, A; Vacelet, T | ||||
| Title | Non-uniform absorption of terahertz radiation on superconducting hot electron bolometer microbridges | Type | Journal Article | ||
| Year | 2014 | Publication | Appl. Phys. Lett. | Abbreviated Journal | <ef><bf><bc>Appl. Phys. Lett. |
| Volume | 104 | Issue | Pages | 052605(1-4) | |
| Keywords | NbN HEB mixers, local oscillator power, RF nonuniform absorption | ||||
| Abstract | We interpret the experimental observation of a frequency-dependence of superconducting hot electron bolometer (HEB) mixers by taking into account the non-uniform absorption of the terahertz radiation on the superconducting HEB microbridge. The radiation absorption is assumed to be proportional to the local surface resistance of the HEB microbridge, which is computed using the Mattis-Bardeen theory. With this assumption the dc and mixing characteristics of a superconducting niobium-nitride (NbN) HEB device have been modeled at frequencies below and above the equilibrium gap frequency of the NbN film. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 935 | |||
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