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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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| Volume | Issue | Pages | |||
| 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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| Address | |||||
| Corporate Author | Thesis | Ph.D. thesis | |||
| Publisher | Chalmers University of Technology | Place of Publication | Göteborg | Editor | |
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 910 | |||
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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 |
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| 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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| Area | Expedition | Conference | |||
| 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 |
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| 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 | Smirnov, K. V.; Vakhtomin, Yu. B.; Divochiy, A. V.; Ozhegov, R. V.; Pentin, I. V.; Gol'tsman, G. N. | ||||
| Title | Infrared and terahertz detectors on basis of superconducting nanostructures | Type | Conference Article | ||
| Year | 2010 | Publication | Microwave and Telecom. Technol. (CriMiCo), 20th Int. Crimean Conf. | Abbreviated Journal |
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| Volume | Issue | Pages | 823-824 | ||
| Keywords | SSPD, SNSPD, HEB | ||||
| Abstract | Results of development of single-photon receiving systems of visible, infrared and terahertz range based on thin-film superconducting nanostructures are presented. The receiving systems are produced on the basis of superconducting nanostructures, which function by means of hot-electron phenomena. | ||||
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| Publisher | Place of Publication | Editor | IEEE | ||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ sasha @ smirnov2010infrared | Serial | 1025 | ||
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| Author | Goltsman, G. N.; Korneev, A. A.; Finkel, M. I.; Divochiy, A. V.; Florya, I. N.; Korneeva, Y. P.; Tarkhov, M. A.; Ryabchun, S. A.; Tretyakov, I. V.; Maslennikov, S. N.; Kaurova, N. S.; Chulkova, G. M.; Voronov, B. M. | ||||
| Title | Superconducting hot-electron bolometer as THz mixer, direct detector and IR single-photon counter | Type | Abstract | ||
| Year | 2010 | Publication | 35th Int. Conf. Infrared, Millimeter, and Terahertz Waves | Abbreviated Journal |
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| Volume | Issue | Pages | 1-1 | ||
| Keywords | SSPD, SNSPD, HEB | ||||
| Abstract | We present a new generation of superconducting single-photon detectors (SSPDs) and hot-electron superconducting sensors with record characteristic for many terahertz and optical applications. | ||||
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| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 2162-2027 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | RPLAB @ sasha @ goltsman2010superconducting | Serial | 1028 | ||
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| Author | Skalare, A.; McGrath, William R.; Echternach, P. M.; Leduc, H. G.; Siddiqi, I.; Verevkin, A.; Prober, D. E. | ||||
| Title | Aluminum hot-electron bolometer mixers at submillimeter wavelengths | Type | Journal Article | ||
| Year | 2001 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal |
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| Volume | 11 | Issue | 1 | Pages | 641-644 |
| Keywords | Al HEB mixer, contacts, interface, in situ, in-situ, Aluminium HEB mixer | ||||
| Abstract | Diffusion-cooled aluminum hot-electron bolometer (HEB) mixers are of interest for low-noise high resolution THz-frequency spectroscopy within astrophysics. Al HEB mixers offer operation with an order of magnitude less local oscillator power, higher intermediate frequency bandwidth and potentially lower noise than competing devices made from other materials. We report on mixer experiments at 618 GHz with devices fabricated from films with sheet resistances in the range from about 55 Ω down to about 9 Ω per square. Intermediate frequency bandwidths of up to 3 GHz were measured (1 μm long device), with absorbed local oscillator power levels of 0.5 to 6 nW and mixer conversion up to -21.5 dB. High input coupling efficiency implies that the electrons in the device are able to thermalize before escaping from the device. It was found that the long coherence length complicates mixer operations due to the proximity of the contact pads. Also, saturation at the IF frequency may be a concern for this type of device, and warrants further studies. | ||||
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| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1051-8223 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | ref919426b | Serial | 1061 | ||
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| Author | Zhang, W.; Miao, W.; Zhong, J. Q.; Shi, S. C.; Hayton, D. J.; Vercruyssen, N.; Gao, J. R.; Goltsman, G. N. | ||||
| Title | Temperature dependence of superconducting hot electron bolometers | Type | Conference Article | ||
| Year | 2013 | Publication | Not published results: 24th international symposium on space terahertz technology | Abbreviated Journal |
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| Volume | Issue | Pages | |||
| Keywords | HEB | ||||
| Abstract | |||||
| Address | Groningen,The Netherlands | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1067 | |||
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| Author | Cherednichenko, S.; Yagoubov, P.; Il'in, K.; Gol'tsman, G.; Gershenzon, E. | ||||
| Title | Large bandwidth of NbN phonon-cooled hot-electron bolometer mixers | Type | Conference Article | ||
| Year | 1997 | Publication | Proc. 27th Eur. Microwave Conf. | Abbreviated Journal |
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| Volume | 2 | Issue | Pages | 972-977 | |
| Keywords | HEB mixer, fabrication process | ||||
| Abstract | The bandwidth of NbN phonon-cooled hot electron bolometer mixers has been systematically investigated with respect to the film thickness and film quality variation. The films, 2.5 to 10 nm thick, were fabricated on sapphire substrates using DC reactive magnetron sputtering. All devices consisted of several parallel strips, each 1 um wide and 2 um long, placed between Ti-Au contact pads. To measure the gain bandwidth we used two identical BWOs operating in the 120-140 GHz frequency range, one functioning as a local oscillator and the other as a signal source. The majority of the measurements were made at an ambient temperature of 4.2 K with optimal LO and DC bias. The maximum 3 dB bandwidth (about 4 GHz) was achieved for the devices made of films which were 2.5-3.5 nm thick, had a high critical temperature, and high critical current density. A theoretical analysis of bandwidth for these mixers based on the two-temperature model gives a good description of the experimental results if one assumes that the electron temperature is equal to the critical temperature. | ||||
| Address | Jerusalem, Israel | ||||
| Corporate Author | Thesis | ||||
| Publisher | IEEE | Place of Publication | Editor | ||
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| Area | Expedition | Conference | 27th Eur. Microwave Conf. | ||
| Notes | Approved | no | |||
| Call Number | Serial | 1075 | |||
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| Author | Angeluts, A. A.; Bezotosnyi, V. V.; Cheshev, E. A.; Goltsman, G. N.; Finkel, M. I.; Seliverstov, S. V.; Evdokimov, M. N.; Gorbunkov, M. V.; Kitaeva, G. Kh.; Koromyslov, A. L.; Kostryukov, P. V.; Krivonos, M. S.; Lobanov, Yu. V.; Shkurinov, A. P.; Sarkisov, S. Yu.; Tunkin, V. G. | ||||
| Title | Compact 1.64 THz source based on a dual-wavelength diode end-pumped Nd:YLF laser with a nearly semiconfocal cavity | Type | Journal Article | ||
| Year | 2014 | Publication | Laser Phys. Lett. | Abbreviated Journal |
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| Volume | 11 | Issue | 1 | Pages | 015004 (1 to 4) |
| Keywords | HEB applications, HEB detector applications, short THz pulses detection | ||||
| Abstract | We describe a compact dual-wavelength (1.047 and 1.053 μm) diode end-pumped Q-switched Nd:YLE laser source which has a number of applications in demand. In order to achieve its dual-wavelength operation it is suggested for the first time to use essentially nonmonotonous dependences of the threshold pump powers at these wavelengths on the cavity length in the region of the cavity semiconfocal configuration under a radius of the pump beam smaller than the radius of the zero Gaussian mode. Here we demonstrate one of the most interesting applications for this laser: difference frequency generation in a GaSe crystal at a frequency of 1.64 THz. A superconducting hot-electron bolometer is used to detect the THz power generated and to measure its pulse characteristics. | ||||
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1076 | |||
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| Author | Benz, A. O.; Bruderer, S.; van Dishoeck, E. F.; Stäuber, P.; Wampfler, S. F.; Melchior, M.; Dedes, C.; Wyrowski, F.; Doty, S. D.; van der Tak, F.; Bächtold, W.; Csillaghy, A.; Megej, A.; Monstein, C.; Soldati, M.; 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.; Dieleman, P.; Dominik, C.; Encrenaz, P.; Fich, M.; Fuente, A.; Giannini, T.; Goicoechea, J. R.; de Graauw, Th.; Helmich, F.; Herczeg, G. J.; Herpin, F.; Hogerheijde, M. R.; Jacq, T.; Jellema, W.; 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.; Ossenkopf, V.; Parise, B.; Pearson, J. C.; Plume, R.; Risacher, C.; Santiago-García, J.; Saraceno, P.; Schieder, R.; Shipman, R.; Stutzki, J.; Tafalla, M.; Tielens, A. G. G. M.; van Kempen, T. A.; Visser, R.; Yıldız, U. A. | ||||
| Title | Hydrides in young stellar objects: Radiation tracers in a protostar-disk-outflow system | Type | Journal Article | ||
| Year | 2010 | Publication | Astron. Astrophys. | Abbreviated Journal |
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| Volume | 521 | Issue | Pages | L35 (1 to 5) | |
| Keywords | HEB mixer applications, HIFI, Herschel | ||||
| Abstract | Context. Hydrides of the most abundant heavier elements are fundamental molecules in cosmic chemistry. Some of them trace gas irradiated by UV or X-rays. Aims. We explore the abundances of major hydrides in W3 IRS5, a prototypical region of high-mass star formation. Methods. W3 IRS5 was observed by HIFI on the Herschel Space Observatory with deep integration (2500 s) in 8 spectral regions. Results. The target lines including CH, NH, H3O+, and the new molecules SH+, H2O+, and OH+ are detected. The H2O+ and OH+ J = 1–0 lines are found mostly in absorption, but also appear to exhibit weak emission (P-Cyg-like). Emission requires high density, thus originates most likely near the protostar. This is corroborated by the absence of line shifts relative to the young stellar object (YSO). In addition, H2O+ and OH+ also contain strong absorption components at a velocity shifted relative to W3 IRS5, which are attributed to foreground clouds. Conclusions. The molecular column densities derived from observations correlate well with the predictions of a model that assumes the main emission region is in outflow walls, heated and irradiated by protostellar UV radiation. |
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| Notes | Approved | no | |||
| Call Number | Serial | 1082 | |||
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