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Sample records for superconducting bolometer array

  1. Transition edge sensor series array bolometer

    Energy Technology Data Exchange (ETDEWEB)

    Beyer, J, E-mail: joern.beyer@ptb.d [Physikalisch-Technische Bundesanstalt (PTB), Abbestrasse 2-12, D-10587 Berlin (Germany)

    2010-10-15

    A transition edge sensor series array (TES-SA) is an array of identical TESs that are connected in series by low-inductance superconducting wiring. The array elements are equally and well thermally coupled to the absorber and respond to changes in the absorber temperature in synchronization. The TES-SA total resistance increases compared to a single TES while the shape of the superconducting transition is preserved. We are developing a TES-SA with a large number, hundreds to thousands, of array elements with the goal of enabling the readout of a TES-based bolometer operated at 4.2 K with a semiconductor-based amplifier located at room temperature. The noise and dynamic performance of a TES-SA bolometer based on a niobium/aluminum bilayer is analyzed. It is shown that stable readout of the bolometer with a low-noise transimpedance amplifier is feasible.

  2. Transition edge sensor series array bolometer

    International Nuclear Information System (INIS)

    Beyer, J

    2010-01-01

    A transition edge sensor series array (TES-SA) is an array of identical TESs that are connected in series by low-inductance superconducting wiring. The array elements are equally and well thermally coupled to the absorber and respond to changes in the absorber temperature in synchronization. The TES-SA total resistance increases compared to a single TES while the shape of the superconducting transition is preserved. We are developing a TES-SA with a large number, hundreds to thousands, of array elements with the goal of enabling the readout of a TES-based bolometer operated at 4.2 K with a semiconductor-based amplifier located at room temperature. The noise and dynamic performance of a TES-SA bolometer based on a niobium/aluminum bilayer is analyzed. It is shown that stable readout of the bolometer with a low-noise transimpedance amplifier is feasible.

  3. Feedhorn-Coupled Transition-Edge Superconducting Bolometer Arrays for Cosmic Microwave Background Polarimetry

    Science.gov (United States)

    Hubmayr, J.; Austermann, J.; Beall, J.; Becker, D.; Cho, H.-M.; Datta, R.; Duff, S. M.; Grace, E.; Halverson, N.; Henderson, S. W.; hide

    2015-01-01

    NIST produces large-format, dual-polarization-sensitive detector arrays for a broad range of frequencies (30-1400 GHz). Such arrays enable a host of astrophysical measurements. Detectors optimized for cosmic microwave background observations are monolithic, polarization-sensitive arrays based on feedhorn and planar Nb antenna-coupled transition-edge superconducting (TES) bolometers. Recent designs achieve multiband, polarimetric sensing within each spatial pixel. In this proceeding, we describe our multichroic, feedhorn-coupled design; demonstrate performance at 70-380 GHz; and comment on current developments for implementation of these detector arrays in the advanced Atacama Cosmology Telescope receiver

  4. Frequency multiplexed superconducting quantum interference device readout of large bolometer arrays for cosmic microwave background measurements.

    Science.gov (United States)

    Dobbs, M A; Lueker, M; Aird, K A; Bender, A N; Benson, B A; Bleem, L E; Carlstrom, J E; Chang, C L; Cho, H-M; Clarke, J; Crawford, T M; Crites, A T; Flanigan, D I; de Haan, T; George, E M; Halverson, N W; Holzapfel, W L; Hrubes, J D; Johnson, B R; Joseph, J; Keisler, R; Kennedy, J; Kermish, Z; Lanting, T M; Lee, A T; Leitch, E M; Luong-Van, D; McMahon, J J; Mehl, J; Meyer, S S; Montroy, T E; Padin, S; Plagge, T; Pryke, C; Richards, P L; Ruhl, J E; Schaffer, K K; Schwan, D; Shirokoff, E; Spieler, H G; Staniszewski, Z; Stark, A A; Vanderlinde, K; Vieira, J D; Vu, C; Westbrook, B; Williamson, R

    2012-07-01

    A technological milestone for experiments employing transition edge sensor bolometers operating at sub-Kelvin temperature is the deployment of detector arrays with 100s-1000s of bolometers. One key technology for such arrays is readout multiplexing: the ability to read out many sensors simultaneously on the same set of wires. This paper describes a frequency-domain multiplexed readout system which has been developed for and deployed on the APEX-SZ and South Pole Telescope millimeter wavelength receivers. In this system, the detector array is divided into modules of seven detectors, and each bolometer within the module is biased with a unique ∼MHz sinusoidal carrier such that the individual bolometer signals are well separated in frequency space. The currents from all bolometers in a module are summed together and pre-amplified with superconducting quantum interference devices operating at 4 K. Room temperature electronics demodulate the carriers to recover the bolometer signals, which are digitized separately and stored to disk. This readout system contributes little noise relative to the detectors themselves, is remarkably insensitive to unwanted microphonic excitations, and provides a technology pathway to multiplexing larger numbers of sensors.

  5. Fabrication of large NbSi bolometer arrays for CMB applications

    International Nuclear Information System (INIS)

    Ukibe, M.; Belier, B.; Camus, Ph.; Dobrea, C.; Dumoulin, L.; Fernandez, B.; Fournier, T.; Guillaudin, O.; Marnieros, S.; Yates, S.J.C.

    2006-01-01

    Future cosmic microwave background experiments for high-resolution anisotropy mapping and polarisation detection require large arrays of bolometers at low temperature. We have developed a process to build arrays of antenna-coupled bolometers for that purpose. With adjustment of the Nb x Si 1-x alloy composition, the array can be made of high impedance or superconductive (TES) sensors

  6. Fabrication of large NbSi bolometer arrays for CMB applications

    Energy Technology Data Exchange (ETDEWEB)

    Ukibe, M. [AIST, Tsukuba Central 2, Tsukuba, Ibaraki 305-8568 (Japan); CNRS-CSNSM, Bat 104, Orsay Campus F-91405 (France); Belier, B. [CNRS-IEF, Bat 220, Orsay Campus F-91405 (France); Camus, Ph. [CNRS-CRTBT, 25 avenue des Martyrs, Grenoble F-38042 (France)]. E-mail: philippe.camus@grenoble.cnrs.fr; Dobrea, C. [CNRS-CSNSM, Bat 104, Orsay Campus F-91405 (France); Dumoulin, L. [CNRS-CSNSM, Bat 104, Orsay Campus F-91405 (France); Fernandez, B. [CNRS-CRTBT, 25 avenue des Martyrs, Grenoble F-38042 (France); Fournier, T. [CNRS-CRTBT, 25 avenue des Martyrs, Grenoble F-38042 (France); Guillaudin, O. [CNRS-LPSC, 53 avenue des Martyrs, Grenoble F-38042 (France); Marnieros, S. [CNRS-CSNSM, Bat 104, Orsay Campus F-91405 (France); Yates, S.J.C. [CNRS-CSNSM, Bat 104, Orsay Campus F-91405 (France)

    2006-04-15

    Future cosmic microwave background experiments for high-resolution anisotropy mapping and polarisation detection require large arrays of bolometers at low temperature. We have developed a process to build arrays of antenna-coupled bolometers for that purpose. With adjustment of the Nb{sub x}Si{sub 1-x} alloy composition, the array can be made of high impedance or superconductive (TES) sensors.

  7. Arrays of membrane isolated yttrium-barium-copper-oxide kinetic inductance bolometers

    International Nuclear Information System (INIS)

    Lindeman, M. A.; Bonetti, J. A.; Bumble, B.; Day, P. K.; Holmes, W. A.; Kleinsasser, A. W.; Eom, B. H.

    2014-01-01

    We are developing of arrays of membrane isolated resonator-bolometers, each with a kinetic inductance device (KID) to measure the temperature of the membrane. The KIDs are fabricated out of the high temperature superconductor YBCO to allow operation at relatively high temperatures. The bolometers are designed to offer higher sensitivity than sensors operating at 300 K, but they require less expensive and lighter weight cooling than even more sensitive conventional superconducting detectors operating at lower temperatures. The bolometer arrays are applicable as focal planes in infrared imaging spectrometers, such as for planetary science missions or earth observing satellites. We describe the devices and present measurements of their sensitivity.

  8. Arrays of membrane isolated yttrium-barium-copper-oxide kinetic inductance bolometers

    Energy Technology Data Exchange (ETDEWEB)

    Lindeman, M. A., E-mail: mark.a.lindeman@jpl.nasa.gov; Bonetti, J. A.; Bumble, B.; Day, P. K.; Holmes, W. A.; Kleinsasser, A. W. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States); Eom, B. H. [California Institute of Technology, Pasadena, California 91125 (United States)

    2014-06-21

    We are developing of arrays of membrane isolated resonator-bolometers, each with a kinetic inductance device (KID) to measure the temperature of the membrane. The KIDs are fabricated out of the high temperature superconductor YBCO to allow operation at relatively high temperatures. The bolometers are designed to offer higher sensitivity than sensors operating at 300 K, but they require less expensive and lighter weight cooling than even more sensitive conventional superconducting detectors operating at lower temperatures. The bolometer arrays are applicable as focal planes in infrared imaging spectrometers, such as for planetary science missions or earth observing satellites. We describe the devices and present measurements of their sensitivity.

  9. 5,120 Superconducting Bolometers for the PIPER Balloon-Borne CMB Polarization Experiment

    Science.gov (United States)

    Benford, Dominic J.; Chuss, David T.; Hilton, Gene C.; Irwin, Kent D.; Jethava, Nikhil S.; Jhabvala, Christine A.; Kogut, Alan J.; Miller, Timothy M.; Mirel, Paul; Moseley, S. Harvey; hide

    2010-01-01

    We are constructing the Primordial Inflation Polarization Explorer (PIPER) to measure the polarization o[ the cosmic microwave background (CMB) and search for the imprint of gravity waves produced during an inflationary epoch in the early universe. The signal is faint and lies behind confusing foregrounds, both astrophysical and cosmological, and so many detectors are required to complete the measurement in a limited time. We will use four of our matured 1,280 pixel, high-filling-factor backshort-under-grid bolometer arrays for efficient operation at the PIPER CMB wavelengths. All four arrays observe at a common wavelength set by passband filters in the optical path. PIPER will fly four times to observe at wavelengths of 1500, 1100, 850, and 500 microns in order to separate CMB from foreground emission. The arrays employ leg-isolated superconducting transition edge sensor bolometers operated at 128mK; tuned resonant backshorts for efficient optical coupling; and a second-generation superconducting quantum interference device (SQUID) multiplexer readout. We describe the design, development, and performance of PIPER bo|ometer array technology to achieve background-limited sensitivity for a cryogenic balloon-borne telescope.

  10. Antenna-coupled bolometer arrays using transition-edge sensors

    Energy Technology Data Exchange (ETDEWEB)

    Myers, Michael J. [Department of Physics, University of California, Berkeley, California 94720 (United States)]. E-mail: mmyers@cosmology.berkeley.edu; Ade, Peter [School of Physics and Astronomy, Cardiff University, Cardiff, Wales (United Kingdom); Arnold, Kam [Department of Physics, University of California, Berkeley, California 94720 (United States); Engargiola, Greg [Department of Astronomy, University of California, Berkeley, California 94720 (United States); Holzapfel, Bill [Department of Physics, University of California, Berkeley, California 94720 (United States); Lee, Adrian T. [Department of Physics, University of California, Berkeley, California 94720 (United States); O' Brient, Roger [Department of Physics, University of California, Berkeley, California 94720 (United States); Richards, Paul L. [Department of Physics, University of California, Berkeley, California 94720 (United States); Smith, Andy [Northrop Grumman, Redondo Beach, California 90278 (United States); Spieler, Helmuth [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Tran, Huan T. [Department of Physics, University of California, Berkeley, California 94720 (United States)

    2006-04-15

    We are developing antenna-coupled Transition-Edge Sensor (TES) bolometer arrays for use in measurements of the CMB polarization. TES bolometers have many well-known advantages over conventional bolometers, such as increased speed, linearity, and the existence of readout multiplexers. Antenna-coupled bolometers use an on-chip planar antenna to couple light into the bolometer. The antenna directivity and polarization sensitivity, along with the potential for on-chip band defining filters and channelizing circuits, allow a significant increase in focal plane integration. This eliminates the bulky horns, quasioptical filters, dichroics, and polarizers which might otherwise be needed in a conventional bolometric system. This simplification will ease the construction of receivers with larger numbers of pixels. We report on the fabrication and optical testing of single antenna-coupled bolometer pixels with integrated band defining filters. We will also discuss current progress on fabrication of a bolometer array based on this design.

  11. Bolometers for far-infrared and submillimetre astronomy

    International Nuclear Information System (INIS)

    Griffin, M.J.

    2000-01-01

    Important scientific goals of far-infrared and submillimetre astronomy include measurements of anisotropies in the cosmic background radiation, deep imaging surveys for detection of high-red-shift galaxies, and imaging and spectroscopy of star formation regions and the interstellar medium in the milky way and nearby galaxies. Use of sensitive bolometer arrays leads to very large improvements in observing speed. Recent progress in the development of bolometric detector systems for ground-based and space-borne far-infrared and submillimetre astronomical observations is reviewed, including spider-web NTD bolometers, transition-edge superconducting sensors, and micromachined planar arrays of ion-implanted silicon bolometers. Future arrays may be based on planar absorbers without feedhorns, which offer potential advantages including more efficient use of space in the focal plane and improved instantaneous sampling of the telescope point spread function, but present challenges in suppression of stray light and RF interference. FIRST and Planck Surveyor are planned satellite missions involving passively cooled (∼70 K) telescopes, and bolometer array developments for these missions are described

  12. Characterization of TES bolometers used in 2-dimensional Backshort-Under-Grid (BUG) arrays for far-infrared astronomy

    International Nuclear Information System (INIS)

    Staguhn, J.G.; Allen, C.A.; Benford, D.J.; Chervenak, J.A.; Chuss, D.T.; Miller, T.M.; Moseley, S.H.; Wollack, E.J.

    2006-01-01

    We have produced a laboratory demonstration of our new Backshort-Under-Grid (BUG) bolometer array architecture in a monolithic, 2-dimensional, 8x8 format. The detector array is designed as a square grid of suspended, 1μm thick silicon bolometers with superconducting molybdium/gold bilayer TESs. These detectors use an additional layer of gold bars deposited on top of the bilayer, oriented transverse to the direction of the current flow, for the suppression of excess noise. This detector design has earlier been shown to provide near fundamental noise limited device performance. We present results from performance measurements of witness devices. In particular we demonstrate that the inband excess noise level of the TES detectors is less than 20% above the thermodynamic phonon noise limit and not significantly higher out of band at frequencies that cannot be attenuated by the Nyquist filter. Our 8x8 BUG arrays will be used in the near future for astronomical observations in several (sub-)millimeter instruments

  13. Recent achievements on the development of the HERSCHEL/PACS bolometer arrays

    International Nuclear Information System (INIS)

    Billot, N.; Agnese, P.; Boulade, O.; Cigna, C.; Doumayrou, E.; Horeau, B.; Lepennec, J.; Martignac, J.; Pornin, J.-L.; Reveret, V.; Rodriguez, L.; Sauvage, M.; Simoens, F.; Vigroux, L.

    2006-01-01

    A new type of bolometer arrays sensitive in the far Infrared and Submillimeter range has been developed and manufactured by CEA/LETI/SLIR since 1997. These arrays will be integrated in the PACS instrument (Photodetector Array Camera and Spectrometer) of ESA's Herschel Space Observatory (launch date 2007). The main innovations of CEA bolometers are their collective manufacturing technique (production of 3-side buttable 16x16 arrays) and their high mapping efficiency (large format detector and instantaneous Nyquist sampling). The measured NEP is 2.10 -16 W/Hz and the thermometric passband about 4-5Hz. In this article we describe CEA bolometers and present the results obtained during the last test campaign

  14. Recent achievements on the development of the HERSCHEL/PACS bolometer arrays

    Energy Technology Data Exchange (ETDEWEB)

    Billot, N. [CEA/Saclay/SAp, UMR CEA/CNRS/UP7 Laboratoire AIM, Bat. 709, l' Orme des merisiers, 91191 Gif-sur-Yvette (France)]. E-mail: nbillot@cea.fr; Agnese, P. [CEA/LETI Grenoble, 17 Avenue des Martyrs, 38054 Grenoble (France); Boulade, O. [CEA/Saclay/SAp, UMR CEA/CNRS/UP7 Laboratoire AIM, Bat. 709, l' Orme des merisiers, 91191 Gif-sur-Yvette (France); Cigna, C. [CEA/LETI Grenoble, 17 Avenue des Martyrs, 38054 Grenoble (France); Doumayrou, E. [CEA/Saclay/SAp, UMR CEA/CNRS/UP7 Laboratoire AIM, Bat. 709, l' Orme des merisiers, 91191 Gif-sur-Yvette (France); Horeau, B. [CEA/Saclay/SAp, UMR CEA/CNRS/UP7 Laboratoire AIM, Bat. 709, l' Orme des merisiers, 91191 Gif-sur-Yvette (France); Lepennec, J. [CEA/Saclay/SAp, UMR CEA/CNRS/UP7 Laboratoire AIM, Bat. 709, l' Orme des merisiers, 91191 Gif-sur-Yvette (France); Martignac, J. [CEA/Saclay/SAp, UMR CEA/CNRS/UP7 Laboratoire AIM, Bat. 709, l' Orme des merisiers, 91191 Gif-sur-Yvette (France); Pornin, J.-L. [CEA/LETI Grenoble, 17 Avenue des Martyrs, 38054 Grenoble (France); Reveret, V. [CEA/Saclay/SAp, UMR CEA/CNRS/UP7 Laboratoire AIM, Bat. 709, l' Orme des merisiers, 91191 Gif-sur-Yvette (France); Rodriguez, L. [CEA/Saclay/SAp, UMR CEA/CNRS/UP7 Laboratoire AIM, Bat. 709, l' Orme des merisiers, 91191 Gif-sur-Yvette (France); Sauvage, M. [CEA/Saclay/SAp, UMR CEA/CNRS/UP7 Laboratoire AIM, Bat. 709, l' Orme des merisiers, 91191 Gif-sur-Yvette (France); Simoens, F. [CEA/LETI Grenoble, 17 Avenue des Martyrs, 38054 Grenoble (France); Vigroux, L. [CEA/Saclay/SAp, UMR CEA/CNRS/UP7 Laboratoire AIM, Bat. 709, l' Orme des merisiers, 91191 Gif-sur-Yvette (France); Institut d' Astrophysique de Paris, 75014 Paris (France)

    2006-11-01

    A new type of bolometer arrays sensitive in the far Infrared and Submillimeter range has been developed and manufactured by CEA/LETI/SLIR since 1997. These arrays will be integrated in the PACS instrument (Photodetector Array Camera and Spectrometer) of ESA's Herschel Space Observatory (launch date 2007). The main innovations of CEA bolometers are their collective manufacturing technique (production of 3-side buttable 16x16 arrays) and their high mapping efficiency (large format detector and instantaneous Nyquist sampling). The measured NEP is 2.10{sup -16}W/Hz and the thermometric passband about 4-5Hz. In this article we describe CEA bolometers and present the results obtained during the last test campaign.

  15. Fabrication of antenna-coupled transition edge polarization-sensitive bolometer arrays

    International Nuclear Information System (INIS)

    Yun, Minhee; Bock, James; Leduc, Henry; Day, Peter; Kim, Moon J.

    2004-01-01

    We have fabricated antenna-coupled superconducting transition edge sensor (TES) arrays for far-infrared and millimeter-wave applications. The advantage of antenna coupling is that the large optical coupling structure required for far-infrared/millimeter wavelengths is not thermally active. The sensor can thus be as small as lithographic techniques permit. By eliminating large absorbers, this technology enables bolometers working at frequencies as low as 30 GHz, covering the entire spectral region of interest for future space-borne studies of cosmic microwave background polarization. We developed a focal plane architecture with dual-polarization sensitivity in a single spectral band, or single-polarization sensitivity in multiple spectral bands. We use TES layers consisting of Al/Ti/Au/Ti thin films and Nb electrical contacts on a low-stress Si 3 N 4 membrane

  16. Superconducting cuprate heterostructures for hot electron bolometers

    Science.gov (United States)

    Wen, B.; Yakobov, R.; Vitkalov, S. A.; Sergeev, A.

    2013-11-01

    Transport properties of the resistive state of quasi-two dimensional superconducting heterostructures containing ultrathin La2-xSrxCuO4 layers synthesized using molecular beam epitaxy are studied. The electron transport exhibits strong deviation from Ohm's law, δV ˜γI3, with a coefficient γ(T) that correlates with the temperature variation of the resistivity dρ /dT. Close to the normal state, analysis of the nonlinear behavior in terms of electron heating yields an electron-phonon thermal conductance per unit area ge -ph≈1 W/K cm2 at T = 20 K, one-two orders of magnitude smaller than in typical superconductors. This makes superconducting LaSrCuO heterostructures to be attractive candidate for the next generation of hot electron bolometers with greatly improved sensitivity.

  17. Superconducting cuprate heterostructures for hot electron bolometers

    International Nuclear Information System (INIS)

    Wen, B.; Yakobov, R.; Vitkalov, S. A.; Sergeev, A.

    2013-01-01

    Transport properties of the resistive state of quasi-two dimensional superconducting heterostructures containing ultrathin La 2−x Sr x CuO 4 layers synthesized using molecular beam epitaxy are studied. The electron transport exhibits strong deviation from Ohm's law, δV∼γI 3 , with a coefficient γ(T) that correlates with the temperature variation of the resistivity dρ/dT. Close to the normal state, analysis of the nonlinear behavior in terms of electron heating yields an electron-phonon thermal conductance per unit area g e−ph ≈1 W/K cm 2 at T = 20 K, one-two orders of magnitude smaller than in typical superconductors. This makes superconducting LaSrCuO heterostructures to be attractive candidate for the next generation of hot electron bolometers with greatly improved sensitivity

  18. Non-uniform absorption of terahertz radiation on superconducting hot electron bolometer microbridges

    International Nuclear Information System (INIS)

    Miao, W.; Zhang, W.; Zhong, J. Q.; Shi, S. C.; Delorme, Y.; Lefevre, R.; Feret, A.; Vacelet, T.

    2014-01-01

    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

  19. The detector calibration system for the CUORE cryogenic bolometer array

    Energy Technology Data Exchange (ETDEWEB)

    Cushman, Jeremy S., E-mail: jeremy.cushman@yale.edu [Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 (United States); Dally, Adam [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Davis, Christopher J. [Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 (United States); Ejzak, Larissa; Lenz, Daniel [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Lim, Kyungeun E. [Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 (United States); Heeger, Karsten M., E-mail: karsten.heeger@yale.edu [Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 (United States); Maruyama, Reina H. [Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 (United States); Nucciotti, Angelo [Dipartimento di Fisica, Università di Milano-Bicocca, Milano I-20126 (Italy); INFN – Sezione di Milano Bicocca, Milano I-20126 (Italy); Sangiorgio, Samuele [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Wise, Thomas [Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 (United States); Department of Physics, University of Wisconsin, Madison, WI 53706 (United States)

    2017-02-01

    The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale cryogenic experiment designed to search for neutrinoless double-beta decay of {sup 130}Te and other rare events. The CUORE detector consists of 988 TeO{sub 2} bolometers operated underground at 10 mK in a dilution refrigerator at the Laboratori Nazionali del Gran Sasso. Candidate events are identified through a precise measurement of their energy. The absolute energy response of the detectors is established by the regular calibration of each individual bolometer using gamma sources. The close-packed configuration of the CUORE bolometer array combined with the extensive shielding surrounding the detectors requires the placement of calibration sources within the array itself. The CUORE Detector Calibration System is designed to insert radioactive sources into and remove them from the cryostat while respecting the stringent heat load, radiopurity, and operational requirements of the experiment. This paper describes the design, commissioning, and performance of this novel source calibration deployment system for ultra-low-temperature environments.

  20. An array of cold-electron bolometers with SIN tunnel junctions and JFET readout for cosmology instruments

    International Nuclear Information System (INIS)

    Kuzmin, L

    2008-01-01

    A novel concept of the parallel/series array of Cold-Electron Bolometers (CEB) with Superconductor-Insulator-Normal (SIN) Tunnel Junctions has been proposed. The concept was developed specially for matching the CEB with JFET amplifier at conditions of high optical power load. The CEB is a planar antenna-coupled superconducting detector with high sensitivity. For combination of effective HF operation and low noise properties the current-biased CEBs are connected in series for DC and in parallel for HF signal. A signal is concentrated from an antenna to the absorber through the capacitance of the tunnel junctions and through additional capacitance for coupling of superconducting islands. Using array of CEBs the applications can be considerably extended to higher power load by distributing the power between N CEBs and decreasing the electron temperature. Due to increased responsivity the noise matching is so effective that photon NEP could be easily achieved at 300 mK with a room temperature JFET for wide range of optical power loads. The concept of the CEB array has been developed for the BOOMERanG balloon telescope and other Cosmology instruments

  1. Design and fabrication of two-dimensional semiconducting bolometer arrays for HAWC and SHARC-II

    Science.gov (United States)

    Voellmer, George M.; Allen, Christine A.; Amato, Michael J.; Babu, Sachidananda R.; Bartels, Arlin E.; Benford, Dominic J.; Derro, Rebecca J.; Dowell, C. D.; Harper, D. A.; Jhabvala, Murzy D.; Moseley, S. H.; Rennick, Timothy; Shirron, Peter J.; Smith, W. W.; Staguhn, Johannes G.

    2003-02-01

    The High resolution Airborne Wideband Camera (HAWC) and the Submillimeter High Angular Resolution Camera II (SHARC II) will use almost identical versions of an ion-implanted silicon bolometer array developed at the National Aeronautics and Space Administration's Goddard Space Flight Center (GSFC). The GSFC "Pop-Up" Detectors (PUD's) use a unique folding technique to enable a 12 × 32-element close-packed array of bolometers with a filling factor greater than 95 percent. A kinematic Kevlar suspension system isolates the 200 mK bolometers from the helium bath temperature, and GSFC - developed silicon bridge chips make electrical connection to the bolometers, while maintaining thermal isolation. The JFET preamps operate at 120 K. Providing good thermal heat sinking for these, and keeping their conduction and radiation from reaching the nearby bolometers, is one of the principal design challenges encountered. Another interesting challenge is the preparation of the silicon bolometers. They are manufactured in 32-element, planar rows using Micro Electro Mechanical Systems (MEMS) semiconductor etching techniques, and then cut and folded onto a ceramic bar. Optical alignment using specialized jigs ensures their uniformity and correct placement. The rows are then stacked to create the 12 × 32-element array. Engineering results from the first light run of SHARC II at the Caltech Submillimeter Observatory (CSO) are presented.

  2. Far infrared through millimeter backshort-under-grid arrays

    Science.gov (United States)

    Allen, Christine A.; Abrahams, John; Benford, Dominic J.; Chervenak, James A.; Chuss, David T.; Staguhn, Johannes G.; Miller, Timothy M.; Moseley, S. Harvey; Wollack, Edward J.

    2006-06-01

    We are developing a large-format, versatile, bolometer array for a wide range of infrared through millimeter astronomical applications. The array design consists of three key components - superconducting transition edge sensor bolometer arrays, quarter-wave reflective backshort grids, and Superconducting Quantum Interference Device (SQUID) multiplexer readouts. The detector array is a filled, square grid of bolometers with superconducting sensors. The backshort arrays are fabricated separately and are positioned in the etch cavities behind the detector grid. The grids have unique three-dimensional interlocking features micromachined into the walls for positioning and mechanical stability. The ultimate goal of the program is to produce large-format arrays with background-limited sensitivity, suitable for a wide range of wavelengths and applications. Large-format (kilopixel) arrays will be directly indium bump bonded to a SQUID multiplexer circuit. We have produced and tested 8×8 arrays of 1 mm detectors to demonstrate proof of concept. 8×16 arrays of 2 mm detectors are being produced for a new Goddard Space Flight Center instrument. We have also produced models of a kilopixel detector grid and dummy multiplexer chip for bump bonding development. We present detector design overview, several unique fabrication highlights, and assembly technologies.

  3. Backshort-Under-Grid arrays for infrared astronomy

    Science.gov (United States)

    Allen, C. A.; Benford, D. J.; Chervenak, J. A.; Chuss, D. T.; Miller, T. M.; Moseley, S. H.; Staguhn, J. G.; Wollack, E. J.

    2006-04-01

    We are developing a kilopixel, filled bolometer array for space infrared astronomy. The array consists of three individual components, to be merged into a single, working unit; (1) a transition edge sensor bolometer array, operating in the milliKelvin regime, (2) a quarter-wave backshort grid, and (3) superconducting quantum interference device multiplexer readout. The detector array is designed as a filled, square grid of suspended, silicon bolometers with superconducting sensors. The backshort arrays are fabricated separately and will be positioned in the cavities created behind each detector during fabrication. The grids have a unique interlocking feature machined into the walls for positioning and mechanical stability. The spacing of the backshort beneath the detector grid can be set from ˜30 300 μm, by independently adjusting two process parameters during fabrication. The ultimate goal is to develop a large-format array architecture with background-limited sensitivity, suitable for a wide range of wavelengths and applications, to be directly bump bonded to a multiplexer circuit. We have produced prototype two-dimensional arrays having 8×8 detector elements. We present detector design, fabrication overview, and assembly technologies.

  4. Bolometer

    International Nuclear Information System (INIS)

    Zasavithi, Efim; Sidorenco, Anatolii

    2011-01-01

    The invention relates to the cooled infrared detectors and can be used in spectroscopy, radiometry, geophysics, astrophysics. The bolometer contains a helium cryostat, in which is installed a solenoid for creation of a magnetic field, connected to a power supply. In the solenoid is placed a superconducting sensor, made of lead telluride doped with thallium Pb 1-x Tl x Te, where x = 0.01...0.0225, to which is connected a recording device. The result of the invention consists in obtaining a stable mode of operation of the bolometer.

  5. Performance of a low-noise test facility for the SAFARI TES bolometer arrays

    NARCIS (Netherlands)

    Audley, M.D.; De Lange, G.; Ferrari, L.; Gao, J.R.; Hijmering, R.A.; Khosropanah, P.; Lindeman, M.; Ridder, M.L.

    2012-01-01

    We have constructed a test facility for characterizing the focal plane arrays of SAFARI, the far-infrared imaging spectrometer for the SPICA satellite. SAFARI’s three bolometer arrays are populated with extremely sensitive (NEP ? 2 × 10?19 W/? Hz) transition edge sensors with a transition

  6. Performance of a Low-Noise Test Facility for the SAFARI TES Bolometer Arrays

    NARCIS (Netherlands)

    Audley, M. D.; de Lange, G.; Ferrari, L.; Gao, J-R.; Hijmering, R. A.; Khosropanah, P.; Lindeman, M.; de Ridder, M.

    We have constructed a test facility for characterizing the focal plane arrays of SAFARI, the far-infrared imaging spectrometer for the SPICA satellite. SAFARI's three bolometer arrays are populated with extremely sensitive (NEP similar to 2 x 10(-19) W/root Hz) transition edge sensors with a

  7. Bolometer

    International Nuclear Information System (INIS)

    Sidorenko, Anatolie; Zasavitchi, Efim

    2007-01-01

    The invention relates to the cooled infra-red radiation detectors and may be used in spectroscopy, radiometry, geophysics and astrophysics. The bolometer contains a helium refrigerator, wherein it is installed a superconductive sensing element, to which it is connected a recording device. Novelty of the invention consists in that into the refrigerator it is placed a temperature control, and the superconductive sensing element is made of a semiconductor, for example, of lead tellurium doped with thallium Pb 1-x Tl x Te, where x=0,01...0,0225.

  8. MgB2-Based Bolometer Array for Far Infra-Red Thermal Imaging and Fourier Transform Spectroscopy Applications

    Science.gov (United States)

    Lakew, B.; Aslam, S.; Brasunas, J.

    2012-01-01

    The mid-superconducting critical temperature (T(sub c) approximately 39 K) of the simple binary, intermetallic MgB, [1] makes it a very good candidate for the development of the next generation of electrooptical devices (e.g. [2]). In particular, recent advances in thin film deposition teclmiques to attain higb quality polycrystalline thin film MgB, deposited on SiN-Si substrates, with T(sub c) approximately 38K [3] coupled with the low voltage noise performance of the film [4] makes it higbly desirable for the development of moderately cooled bolometer arrays for integration into future space-bourne far infra-red (FIR) spectrometers and thermal mappers for studying the outer planets, their icy moons and other moons of interest in the 17-250 micrometer spectral wavelength range. Presently, commercially available pyroelectric detectors operating at 300 K have specific detectivity, D(*), around 7 x 10(exp 8) to 2 x 10(exp 9) centimeters square root of Hz/W. However, a MgB2 thin film based bolometer using a low-stress (less than 140 MPa) SiN membrane isolated from the substrate by a small thermal conductive link, operating at 38 K, promises to have two orders of magnitude higher specific detectivity [5][6].

  9. A scintillating bolometer array for double beta decay studies: The LUCIFER experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gironi, L., E-mail: luca.gironi@mib.infn.it [Università degli Studi di Milano-Bicocca, Milano (Italy); INFN – Sezione di Milano-Bicocca, Milano (Italy)

    2016-07-11

    The main goal of the LUCIFER experiment is to study the neutrinoless double beta decay, a rare process allowed if neutrinos are Majorana particles. Although aiming at a discovery, in the case of insufficient sensitivity the LUCIFER technique will be the demonstrator for a higher mass experiment able to probe the entire inverted hierarchy region of the neutrino mass. In order to achieve this challenging result, high resolution detectors with active background discrimination capability are required. This very interesting possibility can be largely fulfilled by scintillating bolometers thanks to the simultaneous read-out of heat and light emitted by the interactions in the detector or by pulse shape analysis. - Highlights: • The LUCIFER technique will be the demonstrator for a higher mass experiment. • Scintillating bolometers allow high energy resolution and background discrimination. • The first choice for the LUCIFER tower are ZnSe crystals. • The LUCIFER setup will consist of an array of 30 individual single module detectors. • An array of ZnMoO4 crystals allowed the bolometric observation of the 2vDBD of {sup 100}Mo.

  10. Calibration of a novel type of bolometer arrays for the Herschel space observatory

    International Nuclear Information System (INIS)

    Billot, Nicolas

    2007-01-01

    The Herschel mission is a major project at the core of the European Space Agency (ESA) scientific program. The space telescope will perform observations of the universes in the far-infrared regime of the electromagnetic spectrum, which still remains little-known today. Among the many research institutes involved in the development and exploitation of this challenging observatory, the CEA designed a novel type of bolometric detectors to equip the photometer of the PACS instrument on-board the Herschel satellite. During my thesis, my task was twofold, I developed a characterisation procedure that takes advantage of unique features of CEA filled bolometer arrays and I applied it to calibrate the PACS photometer and optimize its performances in the various observing modes open to the scientific community. In this manuscript, I present the basics of infrared astronomy from its very beginning in 1800 to the European Space Agency's Herschel Space Observatory. Then, I describe past and present developments in cryogenic bolometers, emphasising new concepts introduced by CEA. I follow with an explanation of the working principles of CEA bolometer arrays, a prerequisite to grasp the strategy of the characterisation procedure that we developed. Then I expose and analyse thoroughly the results that we obtained during the calibration campaign of the PACS photometer. Finally, I express detector performances in terms of 'observational' performances that future PACS users can comprehend. (author) [fr

  11. Advanced Antenna-Coupled Superconducting Detector Arrays for CMB Polarimetry

    Science.gov (United States)

    Bock, James

    2014-01-01

    We are developing high-sensitivity millimeter-wave detector arrays for measuring the polarization of the cosmic microwave background (CMB). This development is directed to advance the technology readiness of the Inflation Probe mission in NASA's Physics of the Cosmos program. The Inflation Probe is a fourth-generation CMB satellite that will measure the polarization of the CMB to astrophysical limits, characterizing the inflationary polarization signal, mapping large-scale structure based on polarization induced by gravitational lensing, and mapping Galactic magnetic fields through measurements of polarized dust emission. The inflationary polarization signal is produced by a background of gravitational waves from the epoch of inflation, an exponential expansion of space-time in the early universe, with an amplitude that depends on the physical mechanism producing inflation. The inflationary polarization signal may be distinguished by its unique 'B-mode' vector properties from polarization from the density variations that predominantly source CMB temperature anisotropy. Mission concepts for the Inflation Probe are being developed in the US, Europe and Japan. The arrays are based on planar antennas that provide integral beam collimation, polarization analysis, and spectral band definition in a compact lithographed format that eliminates discrete fore-optics such as lenses and feedhorns. The antennas are coupled to transition-edge superconducting bolometers, read out with multiplexed SQUID current amplifiers. The superconducting sensors and readouts developed in this program share common technologies with NASA X-ray and FIR detector applications. Our program targets developments required for space observations, and we discuss our technical progress over the past two years and plans for future development. We are incorporating arrays into active sub-orbital and ground-based experiments, which advance technology readiness while producing state of the art CMB

  12. A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer.

    Energy Technology Data Exchange (ETDEWEB)

    Klaassen, T. O. (Delft University of Technology, Lorentzweg, Delft, The Netherlands); Hajenius, M. (Delft University of Technology, Lorentzweg, Delft, The Netherlands); Adam, A. J. L. (Delft University of Technology, Lorentzweg, Delft, The Netherlands); Klapwijk, T. M. (Delft University of Technology, Lorentzweg, Delft, The Netherlands); Baryshev, A. (SRON National Institute for Space Research, Sorbonnelaan, Utrecht, The Netherlands); Kumar, Sushil (Massachusetts Institute of Technology, Cambridge, MA); Baselmans, J. J. A. (SRON National Institute for Space Research, Sorbonnelaan, Utrecht, The Netherlands); Hu, Qing (Massachusetts Institute of Technology, Cambridge, MA); Yang, Z. Q. (SRON National Institute for Space Research, Sorbonnelaan, Utrecht, The Netherlands); Hovenier, J. N. (Delft University of Technology, Lorentzweg, Delft, The Netherlands); Williams, Benjamin S. (Massachusetts Institute of Technology, Cambridge, MA); Gao, J. R. (Delft University of Technology, Lorentzweg, Delft, The Netherlands); Reno, John Louis

    2005-03-01

    We report the first demonstration of an all solid-state heterodyne receiver that can be used for high-resolution spectroscopy above 2 THz suitable for space-based observatories. The receiver uses a NbN superconducting hot-electron bolometer as mixer and a quantum cascade laser operating at 2.8 THz as local oscillator. We measure a double sideband receiver noise temperature of 1400 K at 2.8 THz and 4.2 K, and find that the free-running QCL has sufficient power stability for a practical receiver, demonstrating an unprecedented combination of sensitivity and stability.

  13. UEDGE code comparisons with DIII-D bolometer data

    Energy Technology Data Exchange (ETDEWEB)

    Daniel, J.M.

    1994-12-01

    This paper describes the work done to develop a bolometer post processor that converts volumetric radiated power values taken from a UEDGE solution, to a line integrated radiated power along chords of the bolometers in the DIII-D tokamak. The UEDGE code calculates plasma physics quantities, such as plasma density, radiated power, or electron temperature, and compares them to actual diagnostic measurements taken from the scrape off layer (SOL) and divertor regions of the DIII-D tokamak. Bolometers are devices measuring radiated power within the tokamak. The bolometer interceptors are made up of two complete arrays, an upper array with a vertical view and a lower array with a horizontal view, so that a two dimensional profile of the radiated power may be obtained. The bolometer post processor stores line integrated values taken from UEDGE solutions into a file in tabular format. Experimental data is then put into tabular form and placed in another file. Comparisons can be made between the UEDGE solutions and actual bolometer data. Analysis has been done to determine the accuracy of the plasma physics involved in producing UEDGE simulations.

  14. Very large scale heterogeneous integration (VLSHI) and wafer-level vacuum packaging for infrared bolometer focal plane arrays

    Science.gov (United States)

    Forsberg, Fredrik; Roxhed, Niclas; Fischer, Andreas C.; Samel, Björn; Ericsson, Per; Hoivik, Nils; Lapadatu, Adriana; Bring, Martin; Kittilsland, Gjermund; Stemme, Göran; Niklaus, Frank

    2013-09-01

    Imaging in the long wavelength infrared (LWIR) range from 8 to 14 μm is an extremely useful tool for non-contact measurement and imaging of temperature in many industrial, automotive and security applications. However, the cost of the infrared (IR) imaging components has to be significantly reduced to make IR imaging a viable technology for many cost-sensitive applications. This paper demonstrates new and improved fabrication and packaging technologies for next-generation IR imaging detectors based on uncooled IR bolometer focal plane arrays. The proposed technologies include very large scale heterogeneous integration for combining high-performance, SiGe quantum-well bolometers with electronic integrated read-out circuits and CMOS compatible wafer-level vacuum packing. The fabrication and characterization of bolometers with a pitch of 25 μm × 25 μm that are arranged on read-out-wafers in arrays with 320 × 240 pixels are presented. The bolometers contain a multi-layer quantum well SiGe thermistor with a temperature coefficient of resistance of -3.0%/K. The proposed CMOS compatible wafer-level vacuum packaging technology uses Cu-Sn solid-liquid interdiffusion (SLID) bonding. The presented technologies are suitable for implementation in cost-efficient fabless business models with the potential to bring about the cost reduction needed to enable low-cost IR imaging products for industrial, security and automotive applications.

  15. The GISMO-2 Bolometer Camera

    Science.gov (United States)

    Staguhn, Johannes G.; Benford, Dominic J.; Fixsen, Dale J.; Hilton, Gene; Irwin, Kent D.; Jhabvala, Christine A.; Kovacs, Attila; Leclercq, Samuel; Maher, Stephen F.; Miller, Timothy M.; hide

    2012-01-01

    We present the concept for the GISMO-2 bolometer camera) which we build for background-limited operation at the IRAM 30 m telescope on Pico Veleta, Spain. GISM0-2 will operate Simultaneously in the 1 mm and 2 mm atmospherical windows. The 1 mm channel uses a 32 x 40 TES-based Backshort Under Grid (BUG) bolometer array, the 2 mm channel operates with a 16 x 16 BUG array. The camera utilizes almost the entire full field of view provided by the telescope. The optical design of GISM0-2 was strongly influenced by our experience with the GISMO 2 mm bolometer camera which is successfully operating at the 30m telescope. GISMO is accessible to the astronomical community through the regular IRAM call for proposals.

  16. Testing and assembly of the detectors for the Millimeter Bolometer Array Camera on ACT

    International Nuclear Information System (INIS)

    Marriage, T.A.; Chervenak, J.A.; Doriese, W.B.

    2006-01-01

    The Millimeter Bolometer Array Camera (MBAC) for the Atacama Cosmology Telescope consists of three Transition Edge Sensor (TES) arrays to make simultaneous observations of the Cosmic Microwave Background in three frequency bands. MBAC TESs are NASA Goddard Pop-Up Detectors (PUD) which are read-out by NIST time-domain multiplexers. MBAC is constructed by stacking 1x32 TES columns to form the 32x32 element arrays. The arrays are modular (connectorized) at the 1x32 column level such that array assembly is reversible and camera repair possible. Prior to assembly, each column is tested in a quick (2h) cycling 4 He/ 3 He adsorption refrigerator. Tests include measurements of TES current-voltage curves and TES complex impedance

  17. Testing and assembly of the detectors for the Millimeter Bolometer Array Camera on ACT

    Energy Technology Data Exchange (ETDEWEB)

    Marriage, T.A. [Physics Department, Princeton University, Washington Road, Princeton, NJ 08544 (United States)]. E-mail: marriage@princeton.edu; Chervenak, J.A. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Doriese, W.B. [National Institute of Standards, 325 Broadway, Boulder, CO 80305 (United States)

    2006-04-15

    The Millimeter Bolometer Array Camera (MBAC) for the Atacama Cosmology Telescope consists of three Transition Edge Sensor (TES) arrays to make simultaneous observations of the Cosmic Microwave Background in three frequency bands. MBAC TESs are NASA Goddard Pop-Up Detectors (PUD) which are read-out by NIST time-domain multiplexers. MBAC is constructed by stacking 1x32 TES columns to form the 32x32 element arrays. The arrays are modular (connectorized) at the 1x32 column level such that array assembly is reversible and camera repair possible. Prior to assembly, each column is tested in a quick (2h) cycling {sup 4}He/{sup 3}He adsorption refrigerator. Tests include measurements of TES current-voltage curves and TES complex impedance.

  18. Applied superconductivity. Handbook on devices and applications. Vol. 1 and 2

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, Paul (ed.) [Jena Univ. (Germany). Inst. fuer Festkoerperphysik, AG Tieftemperaturphysik

    2015-07-01

    The both volumes contain the following 12 chapters: 1. Fundamentals; 2. Superconducting Materials; 3. Technology, Preparation, and Characterization (bulk materials, thin films, multilayers, wires, tapes; cooling); 4, Superconducting Magnets; 5. Power Applications (superconducting cables, superconducting current leads, fault current limiters, transformers, SMES and flywheels; rotating machines; SmartGrids); 6. Superconductive Passive Devices (superconducting microwave components; cavities for accelerators; superconducting pickup coils; magnetic shields); 7. Applications in Quantum Metrology (superconducting hot electron bolometers; transition edge sensors; SIS Mixers; superconducting photon detectors; applications at Terahertz frequency; detector readout); 8. Superconducting Radiation and Particle Detectors; 9. Superconducting Quantum Interference (SQUIDs); 10. Superconductor Digital Electronics; 11. Other Applications (Josephson arrays as radiation sources. Tunable microwave devices) and 12. Summary and Outlook (of the superconducting devices).

  19. Applied superconductivity. Handbook on devices and applications. Vol. 1 and 2

    International Nuclear Information System (INIS)

    Seidel, Paul

    2015-01-01

    The both volumes contain the following 12 chapters: 1. Fundamentals; 2. Superconducting Materials; 3. Technology, Preparation, and Characterization (bulk materials, thin films, multilayers, wires, tapes; cooling); 4, Superconducting Magnets; 5. Power Applications (superconducting cables, superconducting current leads, fault current limiters, transformers, SMES and flywheels; rotating machines; SmartGrids); 6. Superconductive Passive Devices (superconducting microwave components; cavities for accelerators; superconducting pickup coils; magnetic shields); 7. Applications in Quantum Metrology (superconducting hot electron bolometers; transition edge sensors; SIS Mixers; superconducting photon detectors; applications at Terahertz frequency; detector readout); 8. Superconducting Radiation and Particle Detectors; 9. Superconducting Quantum Interference (SQUIDs); 10. Superconductor Digital Electronics; 11. Other Applications (Josephson arrays as radiation sources. Tunable microwave devices) and 12. Summary and Outlook (of the superconducting devices).

  20. Construction and calibration of a fast superconducting bolometer for molecular beams detection

    International Nuclear Information System (INIS)

    Gallinaro, G.; Varone, R.

    1975-01-01

    A tin bolometer evaporated on an anodized aluminum block is described. The noise equivalent power of the bolometer is of 10 -13 watt Hzsup(-1/2) and the time constant is 3μ sec. The bolometer is a suitable fast molecular beam detector

  1. Phase-locking of a terahertz solid-state source using a superconducting hot-electron bolometer mixer

    International Nuclear Information System (INIS)

    Miao, W; Zhang, W; Zhou, K M; Li, S L; Zhang, K; Duan, W Y; Yao, Q J; Shi, S C

    2013-01-01

    We report on a scheme whereby the local-oscillator (LO) of a THz heterodyne receiver can be phase-locked by the mixer of the heterodyne receiver. This scheme is demonstrated for the phase-locking of an 847.6 GHz Gunn oscillator and multiplier chain combined source with a superconducting hot-electron bolometer (HEB) mixer. We show that with this technique the phase-locked beat signal can reach a signal-to-noise ratio higher than 70 dB in a resolution bandwidth (RBW) of 1 Hz. This phase-locking scheme should find good use in THz heterodyne spectrometers. (paper)

  2. Carbon Nanotube Bolometer for Absolute FTIR Spectroscopy

    Science.gov (United States)

    Woods, Solomon; Neira, Jorge; Tomlin, Nathan; Lehman, John

    We have developed and calibrated planar electrical-substitution bolometers which employ absorbers made from vertically-aligned carbon nanotube arrays. The nearly complete absorption of light by the carbon nanotubes from the visible range to the far-infrared can be exploited to enable a device with read-out in native units equivalent to optical power. Operated at cryogenic temperatures near 4 K, these infrared detectors are designed to have time constant near 10 ms and a noise floor of about 10 pW. Built upon a micro-machined silicon platform, each device has an integrated heater and thermometer, either a carbon nanotube thermistor or superconducting transition edge sensor, for temperature control. We are optimizing temperature-controlled measurement techniques to enable high resolution spectral calibrations using these devices with a Fourier-transform spectrometer.

  3. Diffusion-Cooled Tantalum Hot-Electron Bolometer Mixers

    Science.gov (United States)

    Skalare, Anders; McGrath, William; Bumble, Bruce; LeDuc, Henry

    2004-01-01

    A batch of experimental diffusion-cooled hot-electron bolometers (HEBs), suitable for use as mixers having input frequencies in the terahertz range and output frequencies up to about a gigahertz, exploit the superconducting/normal-conducting transition in a thin strip of tantalum. The design and operation of these HEB mixers are based on mostly the same principles as those of a prior HEB mixer that exploited the superconducting/normal- conducting transition in a thin strip of niobium and that was described elsewhere.

  4. Mechanical Design and Development of TES Bolometer Detector Arrays for the Advanced ACTPol Experiment

    Science.gov (United States)

    Ward, Jonathan T.; Austermann, Jason; Beall, James A.; Choi, Steve K.; Crowley, Kevin T.; Devlin, Mark J.; Duff, Shannon M.; Gallardo, Patricio M.; Henderson, Shawn W.; Ho, Shuay-Pwu Patty; hide

    2016-01-01

    The next generation Advanced ACTPol (AdvACT) experiment is currently underway and will consist of four Transition Edge Sensor (TES) bolometer arrays, with three operating together, totaling 5800 detectors on the sky. Building on experience gained with the ACTPol detector arrays, AdvACT will utilize various new technologies, including 150 mm detector wafers equipped with multichroic pixels, allowing for a more densely packed focal plane. Each set of detectors includes a feedhorn array of stacked silicon wafers which form a spline pro le leading to each pixel. This is then followed by a waveguide interface plate, detector wafer, back short cavity plate, and backshort cap. Each array is housed in a custom designed structure manufactured from high purity copper and then gold plated. In addition to the detector array assembly, the array package also encloses cryogenic readout electronics. We present the full mechanical design of the AdvACT high frequency (HF) detector array package along with a detailed look at the detector array stack assemblies. This experiment will also make use of extensive hardware and software previously developed for ACT, which will be modi ed to incorporate the new AdvACT instruments. Therefore, we discuss the integration of all AdvACT arrays with pre-existing ACTPol infrastructure.

  5. Superconducting Coset Topological Fluids in Josephson Junction Arrays

    CERN Document Server

    Diamantini, M C; Trugenberger, C A; Sodano, Pasquale; Trugenberger, Carlo A.

    2006-01-01

    We show that the superconducting ground state of planar Josephson junction arrays is a P- and T-invariant coset topological quantum fluid whose topological order is characterized by the degeneracy 2 on the torus. This new mechanism for planar superconductivity is the P- and T-invariant analogue of Laughlin's quantum Hall fluids. The T=0 insulator-superconductor quantum transition is a quantum critical point characterized by gauge fields and deconfined degrees of freedom. Experiments on toroidal Josephson junction arrays could provide the first direct evidence for topological order and superconducting quantum fluids.

  6. New technologies for the detection of millimeter and submillimeter waves

    Science.gov (United States)

    Richards, P. L.; Clarke, J.; Gildemeister, J. M.; Lanting, T.; Lee, A. T.

    2001-01-01

    Voltage-biased superconducting bolometers have many operational advantages over conventional bolometer technology including sensitivity, linearity, speed, and immunity from environmental disturbance. A review is given of the Berkeley program for developing this new technology. Developments include fully lithographed individual bolometers in the spiderweb configuration, arrays of 1024 close-packed absorber-coupled bolometers, antenna-coupled bolometers, and a frequency-domain SQUID (superconducting quantum interference device) readout multiplexer.

  7. Fabrication of prototype imaging arrays for SCUBA-2

    International Nuclear Information System (INIS)

    Hilton, G.C.; Beall, J.A.; Doriese, W.B.; Duncan, W.D.; Ferreira, L.S.; Irwin, K.D.; Reintsema, C.D.; Ullom, J.N.; Vale, L.R.; Xu, Y.; Zink, B.L.; Parkes, W.; Bunting, A.S.; Dunare, C.C.; Gundlach, A.M.; Stevenson, J.T.M.; Walton, A.J.; Schulte, E.; Corrales, E.; Sienicki, J.P.; Bintley, Dan; Ade, P.A.R.; Sudiwala, Rashmi V.; Woodcraft, Adam L.; Halpern, Mark; Holland, W.; Audley, M.D.; MacIntosh, M.

    2006-01-01

    Prototype imaging subarrays for SCUBA-2 (the Submillimeter Common-User Bolometer Array) have been fabricated and tested. The pixel count (1280) of these wafer-scale imagers is significantly larger than any other low-temperature detectors produced to date, and represents a major step forward for the low-temperature detector community. These transition-edge-sensor (TES) based imagers utilize several innovations including in-focal-plane superconducting quantum intereference device (SQUID) multiplexers, micromachined Si block absorbers, and superconducting wafer hybridization. In this paper, we review the fabrication processes developed for these imagers and present recent optical data from a prototype imaging subarray

  8. Optimization study on the magnetic field of superconducting Halbach Array magnet

    Science.gov (United States)

    Shen, Boyang; Geng, Jianzhao; Li, Chao; Zhang, Xiuchang; Fu, Lin; Zhang, Heng; Ma, Jun; Coombs, T. A.

    2017-07-01

    This paper presents the optimization on the strength and homogeneity of magnetic field from superconducting Halbach Array magnet. Conventional Halbach Array uses a special arrangement of permanent magnets which can generate homogeneous magnetic field. Superconducting Halbach Array utilizes High Temperature Superconductor (HTS) to construct an electromagnet to work below its critical temperature, which performs equivalently to the permanent magnet based Halbach Array. The simulations of superconducting Halbach Array were carried out using H-formulation based on B-dependent critical current density and bulk approximation, with the FEM platform COMSOL Multiphysics. The optimization focused on the coils' location, as well as the geometry and numbers of coils on the premise of maintaining the total amount of superconductor. Results show Halbach Array configuration based superconducting magnet is able to generate the magnetic field with intensity over 1 Tesla and improved homogeneity using proper optimization methods. Mathematical relation of these optimization parameters with the intensity and homogeneity of magnetic field was developed.

  9. Quantum noise in a terahertz hot electron bolometer mixer

    NARCIS (Netherlands)

    Zhang, W.; Khosropanah, P.; Gao, J. R.; Kollberg, E. L.; Yngvesson, K. S.; Bansal, T.; Barends, R.; Klapwijk, T. M.

    2010-01-01

    We have measured the noise temperature of a single, sensitive superconducting NbN hot electron bolometer (HEB) mixer in a frequency range from 1.6 to 5.3 THz, using a setup with all the key components in vacuum. By analyzing the measured receiver noise temperature using a quantum noise (QN) model

  10. High-Tc superconducting microbolometer for terahertz applications

    Science.gov (United States)

    Ulysse, C.; Gaugue, A.; Adam, A.; Kreisler, A. J.; Villégier, J.-C.; Thomassin, J.-L.

    2002-05-01

    Superconducting hot electron bolometer mixers are now a competitive alternative to Schottky diode mixers in the terahertz frequency range because of their ultra wideband (from millimeter waves to visible light), high conversion gain, and low intrinsic noise level. High Tc superconductor materials can be used to make hot electron bolometers and present some advantage in term of operating temperature and cooling. In this paper, we present first a model for the study of superconducting hot electron bolometers responsivity in direct detection mode, in order to establish a firm basis for the design of future THz mixers. Secondly, an original process to realize YBaCuO hot electron bolometer mixers will be described. Submicron YBaCuO superconducting structures are expitaxially sputter deposited on MgO substrates and patterned by using electron beam lithography in combination with optical lithography. Metal masks achieved by electron beam lithography are insuring a good bridge definition and protection during ion etching. Finally, detection experiments are being performed with a laser at 850 nm wavelength, in homodyne mode in order to prove the feasibility and potential performances of these devices.

  11. Frequency-domain readout multiplexing of transition-edge sensor arrays

    Energy Technology Data Exchange (ETDEWEB)

    Lanting, T.M. [Physics Department, University of California, Berkeley, CA 94720 (United States)]. E-mail: tlanting@berkeley.edu; Arnold, K. [Physics Department, University of California, Berkeley, CA 94720 (United States); Cho, Hsiao-Mei [Physics Department, University of California, Berkeley, CA 94720 (United States); Clarke, John [Physics Department, University of California, Berkeley, CA 94720 (United States); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Dobbs, Matt [Physics Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Holzapfel, William [Physics Department, University of California, Berkeley, CA 94720 (United States); Lee, Adrian T. [Physics Department, University of California, Berkeley, CA 94720 (United States); Physics Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Lueker, M. [Physics Department, University of California, Berkeley, CA 94720 (United States); Richards, P.L. [Physics Department, University of California, Berkeley, CA 94720 (United States); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Smith, A.D. [Northrop-Grumman, Redondo Beach, CA 94278 (United States); Spieler, H.G. [Physics Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2006-04-15

    We have demonstrated frequency-domain readout multiplexing of eight channels for superconducting transition-edge sensor bolometer arrays. The multiplexed readout noise is 6.5 pA/{radical}Hz, well below the bolometer dark noise of 15-20 pA/{radical}Hz. We measure an upper limit on crosstalk of 0.004 between channels adjacent in frequency which meets our design requirement of 0.01. We have observed vibration insensitivity in our frequency-domain multiplexed transition-edge sensors, making this system very attractive for telescope and satellite observations. We also discuss extensions to our multiplexed readout. In particular, we are developing a SQUID flux-locked loop that is entirely cold and collaborating on digital multiplexer technology in order to scale up the number of multiplexed channels.

  12. Neutron transmutation doped Ge bolometers

    Science.gov (United States)

    Haller, E. E.; Kreysa, E.; Palaio, N. P.; Richards, P. L.; Rodder, M.

    1983-01-01

    Some conclusions reached are as follow. Neutron Transmutation Doping (NTD) of high quality Ge single crystals provides perfect control of doping concentration and uniformity. The resistivity can be tailored to any given bolometer operating temperature down to 0.1 K and probably lower. The excellent uniformity is advantaged for detector array development.

  13. The 160 TES bolometer read-out using FDM for SAFARI

    Science.gov (United States)

    Hijmering, R. A.; den Hartog, R. H.; van der Linden, A. J.; Ridder, M.; Bruijn, M. P.; van der Kuur, J.; van Leeuwen, B. J.; van Winden, P.; Jackson, B.

    2014-07-01

    For the read out of the Transition Edge Sensors (TES) bolometer arrays of the SAFARI instrument on the Japanese background-limited far-IR SPICA mission SRON is developing a Frequency Domain Multiplexing (FDM) read-out system. The next step after the successful demonstration of the read out of 38 TES bolometers using FDM was to demonstrate the FDM readout of the required 160 TES bolometers. Of the 160 LC filter and TES bolometer chains 151 have been connected and after cooldown 148 of the resonances could be identified. Although initial operation and locking of the pixels went smoothly the experiment revealed several complications. In this paper we describe the 160 pixel FDM set-up, show the results and discuss the issues faced during operation of the 160 pixel FDM experiment.

  14. Superconducting hot-electron bolometer: from the discovery of hot-electron phenomena to practical applications

    International Nuclear Information System (INIS)

    Shurakov, A; Lobanov, Y; Goltsman, G

    2016-01-01

    The discovery of hot-electron phenomena in a thin superconducting film in the last century was followed by numerous experimental studies of its appearance in different materials aiming for a better understanding of the phenomena and consequent implementation of terahertz detection systems for practical applications. In contrast to the competitors such as superconductor-insulator-superconductor tunnel junctions and Schottky diodes, the hot electron bolometer (HEB) did not demonstrate any frequency limitation of the detection mechanism. The latter, in conjunction with a decent performance, rapidly made the HEB mixer the most attractive candidate for heterodyne observations at frequencies above 1 THz. The successful operation of practical instruments (the Heinrich Hertz Telescope, the Receiver Lab Telescope, APEX, SOFIA, Hershel) ensures the importance of the HEB technology despite the lack of rigorous theoretical routine for predicting the performance. In this review, we provide a summary of experimental and theoretical studies devoted to understanding the HEB physics, and an overview of various fabrication routes and materials. (topical review)

  15. Investigations of two types of superconducting arrays

    International Nuclear Information System (INIS)

    Niu, M.

    1993-01-01

    This dissertation has two parts. Part one studies the anisotropy effect on homogeneous superconducting wire-networks, by using the Abrikosov approach. The networks assumed to have an infinite square lattice geometry. An anisotropy parameter R is defined to be the cross sectional area ratio of the vertical and horizontal strands. Many limiting behaviors of the order parameter distribution as R → ∞ are obtained. Many anisotropy-induced vortex configurational transitions are found at several Φ/Φ 0 values studied, and are investigated in detail. Part two studies the ground-state vortex configurations of the Josephson-coupled arrays of superconducting islands. The Ginzburg-Landau Josephson array model is used. With arrays of Penrose tiling geometry, the authors have found negative evidences against a proposed mechanism, and positive evidences for a new mechanism for generating commensurate states. But the mechanisms for the majority of the nontrivial commensurate states remain to be investigated. With arrays of infinite square lattice geometry, a temperature-induced vortex configurational transition at Φ/Φ 0 = 1/6 is found. The authors discover that the equilibrium vortex ground state of an infinite square-lattice array can occur in a unit cell of size other than q by q, or 2q by 2q, which has been widely accepted and commonly used so far

  16. Terahertz hot electron bolometer waveguide mixers for GREAT

    OpenAIRE

    Pütz, P.; Honingh, C. E.; Jacobs, K.; Justen, M.; Schultz, M.; Stutzki, J.

    2012-01-01

    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. 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 the...

  17. Superconducting Hot-Electron Submillimeter-Wave Detector

    Science.gov (United States)

    Karasik, Boris; McGrath, William; Leduc, Henry

    2009-01-01

    A superconducting hot-electron bolometer has been built and tested as a prototype of high-sensitivity, rapid-response detectors of submillimeter-wavelength radiation. There are diverse potential applications for such detectors, a few examples being submillimeter spectroscopy for scientific research; detection of leaking gases; detection of explosive, chemical, and biological weapons; and medical imaging. This detector is a superconducting-transition- edge device. Like other such devices, it includes a superconducting bridge that has a low heat capacity and is maintained at a critical temperature (T(sub c)) at the lower end of its superconducting-transition temperature range. Incident photons cause transient increases in electron temperature through the superconducting-transition range, thereby yielding measurable increases in electrical resistance. In this case, T(sub c) = 6 K, which is approximately the upper limit of the operating-temperature range of silicon-based bolometers heretofore used routinely in many laboratories. However, whereas the response speed of a typical silicon- based laboratory bolometer is characterized by a frequency of the order of a kilohertz, the response speed of the present device is much higher characterized by a frequency of the order of 100 MHz. For this or any bolometer, a useful figure of merit that one seeks to minimize is (NEP)(tau exp 1/2), where NEP denotes the noise-equivalent power (NEP) and the response time. This figure of merit depends primarily on the heat capacity and, for a given heat capacity, is approximately invariant. As a consequence of this approximate invariance, in designing a device having a given heat capacity to be more sensitive (to have lower NEP), one must accept longer response time (slower response) or, conversely, in designing it to respond faster, one must accept lower sensitivity. Hence, further, in order to increase both the speed of response and the sensitivity, one must make the device very small in

  18. Superconductivity of a Sn film controlled by an array of Co nanowires

    Science.gov (United States)

    Wei, Z.; Ye, Z.; Rathnayaka, K. D. D.; Lyuksyutov, I. F.; Wu, W.; Naugle, D. G.

    2012-09-01

    Superconducting properties of a hybrid structure composed of ferromagnetic Co nanowire arrays and a superconducting Sn film have been investigated. Ordered Co nanowires arrays with 60 nm, 150 nm and 200 nm diameter were electroplated into the pores of self organized Anodic Aluminum Oxide (AAO) membranes. Hysteretic dependence of the Sn film superconducting properties on applied magnetic field and critical current enhancement at moderate fields has been observed. This behavior strongly depends on the ratio of the Sn film thickness to the Co nanowire diameter.

  19. Superconductivity of a Sn film controlled by an array of Co nanowires

    International Nuclear Information System (INIS)

    Wei, Z.; Ye, Z.; Rathnayaka, K.D.D.; Lyuksyutov, I.F.; Wu, W.; Naugle, D.G.

    2012-01-01

    Superconducting properties of a hybrid structure composed of ferromagnetic Co nanowire arrays and a superconducting Sn film have been investigated. Ordered Co nanowires arrays with 60 nm, 150 nm and 200 nm diameter were electroplated into the pores of self organized Anodic Aluminum Oxide (AAO) membranes. Hysteretic dependence of the Sn film superconducting properties on applied magnetic field and critical current enhancement at moderate fields has been observed. This behavior strongly depends on the ratio of the Sn film thickness to the Co nanowire diameter.

  20. SUPERCONDUCTING QUADRUPOLE ARRAYS FOR MULTIPLE BEAM TRANSPORT

    International Nuclear Information System (INIS)

    Rainer Meinke Carl Goodzeit Penny Ball Roger Bangerter

    2003-01-01

    The goal of this research was to develop concepts for affordable, fully functional arrays of superconducting quadrupoles for multi-beam transport and focusing in heavy ion fusion (HIF)accelerators. Previous studies by the Virtual National Laboratory (VNL) collaboration have shown that the multi-beam transport system (consisting of alternating gradient quadrupole magnets, a beam vacuum system, and the beam monitor and control system) will likely be one of the most expensive and critical parts of such an accelerator. This statement is true for near-term fusion research accelerators as well as accelerators for the ultimate goal of power production via inertial fusion. For this reason, research on superconducting quadrupole arrays is both timely and important for the inertial fusion energy (IFE) research program. This research will also benefit near-term heavy ion fusion facilities such as the Integrated Research Experiment (IRE)and/or the Integrated Beam Experiment (IBX). We considered a 2-prong approach that addresses the needs of both the nearer and longer term requirements of the inertial fusion program. First, we studied the flat coil quadrupole design that was developed by LLNL; this magnet is 150 mm long with a 50 mm aperture and thus is suitable for near term experiments that require magnets of a small length to aperture ratio. Secondly, we studied the novel double-helix quadrupole (DHQ) design in a small (3 x 3) array configuration; this design can provide an important step to the longer term solution of loW--cost, easy to manufacture array constructions. Our Phase I studies were performed using the AMPERES magnetostatic analysis software. Consideration of these results led to plans for future magnet RandD construction projects. The first objective of Phase I was to develop the concept of a superconducting focusing array that meets the specific requirements of a heavy ion fusion accelerator. Detailed parameter studies for such quadrupole arrays were performed

  1. SUPERCONDUCTING QUADRUPOLE ARRAYS FOR MULTIPLE BEAM TRANSPORT

    Energy Technology Data Exchange (ETDEWEB)

    Rainer Meinke

    2003-10-01

    The goal of this research was to develop concepts for affordable, fully functional arrays of superconducting quadrupoles for multi-beam transport and focusing in heavy ion fusion (HIF)accelerators. Previous studies by the Virtual National Laboratory (VNL) collaboration have shown that the multi-beam transport system (consisting of alternating gradient quadrupole magnets, a beam vacuum system, and the beam monitor and control system) will likely be one of the most expensive and critical parts of such an accelerator. This statement is true for near-term fusion research accelerators as well as accelerators for the ultimate goal of power production via inertial fusion. For this reason, research on superconducting quadrupole arrays is both timely and important for the inertial fusion energy (IFE) research program. This research will also benefit near-term heavy ion fusion facilities such as the Integrated Research Experiment (IRE)and/or the Integrated Beam Experiment (IBX). We considered a 2-prong approach that addresses the needs of both the nearer and longer term requirements of the inertial fusion program. First, we studied the flat coil quadrupole design that was developed by LLNL; this magnet is 150 mm long with a 50 mm aperture and thus is suitable for near term experiments that require magnets of a small length to aperture ratio. Secondly, we studied the novel double-helix quadrupole (DHQ) design in a small (3 x 3) array configuration; this design can provide an important step to the longer term solution of low-cost, easy to manufacture array constructions. Our Phase I studies were performed using the AMPERES magnetostatic analysis software. Consideration of these results led to plans for future magnet R&D construction projects. The first objective of Phase I was to develop the concept of a superconducting focusing array that meets the specific requirements of a heavy ion fusion accelerator. Detailed parameter studies for such quadrupole arrays were performed

  2. Ultrathin NbN film superconducting single-photon detector array

    International Nuclear Information System (INIS)

    Smirnov, K; Korneev, A; Minaeva, O; Divochiy, A; Tarkhov, M; Ryabchun, S; Seleznev, V; Kaurova, N; Voronov, B; Gol'tsman, G; Polonsky, S

    2007-01-01

    We report on the fabrication process of the 2 x 2 superconducting single-photon detector (SSPD) array. The SSPD array is made from ultrathin NbN film and is operated at liquid helium temperatures. Each detector is a nanowire-based structure patterned by electron beam lithography process. The advances in fabrication technology allowed us to produce highly uniform strips and preserve superconducting properties of the unpatterned film. SSPD exhibit up to 30% quantum efficiency in near infrared and up to 1% at 5-μm wavelength. Due to 120 MHz counting rate and 18 ps jitter, the time-domain multiplexing read-out is proposed for large scale SSPD arrays. Single-pixel SSPD has already found a practical application in non-invasive testing of semiconductor very-large scale integrated circuits. The SSPD significantly outperformed traditional single-photon counting avalanche diodes

  3. Noise and specific detectivity measurements on high-temperature superconducting transition-edge bolometers

    International Nuclear Information System (INIS)

    Black, R.D.; Mogro-campero, A.; Turner, L.G.

    1990-01-01

    The effects of thermal fluctuation noise in thermal detectors can be lessened by reducing heat capacity and thermal conductance. An attempt to accomplish this with the YBa2Cu3O(7-x) (YBCO) bolometer by making YBCO resistors on thermally isolated membranes is reported. The spectral power of the electrical noise of YBCO films on SrTiO3, bulk silicon with a buffer layer, and in thin dielectric membranes is measured. It is found that 1/f noise predominates in polycrystalline YBCO films on silicon-based substrates. Films on SrTiO3 with good electrical properties are dominated by thermal fluctuation noise, just as in the case of low-temperature superconductors. The implications of these findings for bolometer are addressed. The specific detectivity of a bolometric pixel made on bulk SrTiO3 is reported. 14 refs

  4. Optimized Superconducting Quadrupole Arrays for Multiple Beam Transport

    Energy Technology Data Exchange (ETDEWEB)

    Meinke, Rainer B. [Advanced Magnet Lab, Inc., Melbourne, FL (United States); Goodzeit, Carl L. [Advanced Magnet Lab, Inc., Melbourne, FL (United States); Ball, Millicent J. [Advanced Magnet Lab, Inc., Melbourne, FL (United States)

    2005-09-20

    This research project advanced the development of reliable, cost-effective arrays of superconducting quadrupole magnets for use in multi-beam inertial fusion accelerators. The field in each array cell must be identical and meet stringent requirements for field quality and strength. An optimized compact array design using flat double-layer pancake coils was developed. Analytical studies of edge termination methods showed that it is feasible to meet the requirements for field uniformity in all cells and elimination of stray external field in several ways: active methods that involve placement of field compensating coils on the periphery of the array or a passive method that involves use of iron shielding.

  5. Antenna-coupled 30 THz hot electron bolometer mixers

    OpenAIRE

    Shcherbatenko, M.; Lobanov, Y.; Benderov, O.; Shurakov, A.; Ignatov, A.; Titova, N.; Finkel, M.; Maslennikov, S.; Kaurova, N.; Voronov, B.M.; Rodin, A.; Klapwijk, T.M.; Gol'tsman, G.N.

    2015-01-01

    We report on design and characterization of a superconducting Hot Electron Bolometer Mixer integrated with a logarithmic spiral antenna for mid-IR range observations. The antenna parameters have been adjusted to achieve the ultimate performance at 10 ?m (30 THz) range where O3, NH3, CO2, CH4, N2O, …. lines in the Earth’s atmosphere, in planetary atmospheres and in the interstellar space can be observed. The HEB mixer is made of a thin NbN film deposited onto a GaAs substrate. To couple the ra...

  6. Superconducting Microwave Resonator Arrays for Submillimeter/Far-Infrared Imaging

    Science.gov (United States)

    Noroozian, Omid

    Superconducting microwave resonators have the potential to revolutionize submillimeter and far-infrared astronomy, and with it our understanding of the universe. The field of low-temperature detector technology has reached a point where extremely sensitive devices like transition-edge sensors are now capable of detecting radiation limited by the background noise of the universe. However, the size of these detector arrays are limited to only a few thousand pixels. This is because of the cost and complexity of fabricating large-scale arrays of these detectors that can reach up to 10 lithographic levels on chip, and the complicated SQUID-based multiplexing circuitry and wiring for readout of each detector. In order to make substantial progress, next-generation ground-based telescopes such as CCAT or future space telescopes require focal planes with large-scale detector arrays of 104--10 6 pixels. Arrays using microwave kinetic inductance detectors (MKID) are a potential solution. These arrays can be easily made with a single layer of superconducting metal film deposited on a silicon substrate and pattered using conventional optical lithography. Furthermore, MKIDs are inherently multiplexable in the frequency domain, allowing ˜ 10 3 detectors to be read out using a single coaxial transmission line and cryogenic amplifier, drastically reducing cost and complexity. An MKID uses the change in the microwave surface impedance of a superconducting thin-film microresonator to detect photons. Absorption of photons in the superconductor breaks Cooper pairs into quasiparticles, changing the complex surface impedance, which results in a perturbation of resonator frequency and quality factor. For excitation and readout, the resonator is weakly coupled to a transmission line. The complex amplitude of a microwave probe signal tuned on-resonance and transmitted on the feedline past the resonator is perturbed as photons are absorbed in the superconductor. The perturbation can be

  7. The investigation of the phase-locking stability in linear arrays of Josephson junctions and arrays closed into a superconducting loop

    International Nuclear Information System (INIS)

    Darula, M.; Seidel, P.; Misanik, B.; Busse, F.; Heinz, E.; Benacka, S.

    1994-01-01

    The phase-locking stability is investigated theoretically in two structures: linear arrays of Josephson junctions shunted by resistive load and arrays closed into superconducting loop. In both cases the quasi-identical junctions are supposed to be in arrays. The stability as a function of spread in Josephson junction parameters as well as a function of other circuit parameters is investigated. Using Floquet theory it is shown that spread in critical currents of Josephson junction limit the stability of phase-locking state. From the simulations it follows that the phase-locking in arrays closed into superconducting loop is more stable against the spread in junction parameters than in the case of linear array of Josephson junctions. (orig.)

  8. Superconducting Properties of Lead-Bismuth Films Controlled by Ferromagnetic Nanowire Arrays

    Science.gov (United States)

    Ye, Zuxin; Lyuksyutov, Igor F.; Wu, Wenhao; Naugle, Donald G.

    2011-03-01

    Superconducting properties of lead-bismuth (82% Pb and 18% Bi) alloy films deposited on ferromagnetic nanowire arrays have been investigated. Ferromagnetic Co or Ni nanowires are first electroplated into the columnar pores of anodic aluminum oxide (AAO) membranes. Superconducting Pb 82 Bi 18 films are then quench-condensed onto the polished surface of the AAO membranes filled with magnetic nanowires. A strong dependence of the Pb 82 Bi 18 superconducting properties on the ratio of the superconducting film thickness to the magnetic nanowire diameter and the material variety was observed.

  9. Quantum noise in a terahertz hot electron bolometer mixer

    OpenAIRE

    Zhang, W.; Khosropanah, P.; Gao, J. R.; Kollberg, E. L.; Yngvesson, K. S.; Bansal, T.; Barends, R.; Klapwijk, T. M.

    2010-01-01

    We have measured the noise temperature of a single, sensitive superconducting NbN hot electron bolometer (HEB) mixer in a frequency range from 1.6 to 5.3 THz, using a setup with all the key components in vacuum. By analyzing the measured receiver noise temperature using a quantum noise (QN) model for HEB mixers, we confirm the effect of QN. The QN is found to be responsible for about half of the receiver noise at the highest frequency in our measurements. The ?-factor (the quantum efficiency ...

  10. Enhanced performance of VOx-based bolometer using patterned gold black absorber

    Science.gov (United States)

    Smith, Evan M.; Panjwani, Deep; Ginn, James; Warren, Andrew; Long, Christopher; Figuieredo, Pedro; Smith, Christian; Perlstein, Joshua; Walter, Nick; Hirschmugl, Carol; Peale, Robert E.; Shelton, David J.

    2015-06-01

    Patterned highly absorbing gold black film has been selectively deposited on the active surfaces of a vanadium-oxide-based infrared bolometer array. Patterning by metal lift-off relies on protection of the fragile gold black with an evaporated oxide, which preserves gold black's near unity absorption. This patterned gold black also survives the dry-etch removal of the sacrificial polyimide used to fabricate the air-bridge bolometers. Infrared responsivity is substantially improved by the gold black coating without significantly increasing noise. The increase in the time constant caused by the additional mass of gold black is a modest 14%.

  11. Superconducting Tunnel Junction Arrays for UV Photon Detection, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — An innovative method is described for the fabrication of superconducting tunnel junction (STJ) detector arrays offering true "three dimensional" imaging throughout...

  12. Investigation of the Neutral Gas Pressure Effect on the Metal Resistive Bolometer

    International Nuclear Information System (INIS)

    Zhang, D.; Giannone, L.; Piechotka, M.; Windisch, T.; Klinger, T.; Grulke, O.; Stark, A.

    2008-01-01

    The bolometer system planned for W7-X consists mainly of metal (Au) resistive detector arrays. All the detectors are exposed to neutral gas environment. The thin bolometer foil used for detecting the radiated power loss may be sensitive to the neutral gas pressure due to the strain gauge effect. Recently, a prototype of this kind of bolometer camera consisting of 12 channels has been installed on the cylindrical plasma device VINETA in order to investigate the influences of the neutral gas pressure on the bolometer signals. Experiments are carried out for Ar-discharges under different gas pressure conditions. It is found that the pressure effect of the neutral gas can make considerable contributions, thus inducing non-negligible errors of the results in most of the investigated cases. Using the VINETA plasmas (Ar, T e e -19 m -3 ) as examples, the paper demonstrates and discusses how to minimize the neutral gas effects, especially in the data analysis process. The radiated power and the radiation intensity profile obtained in helicon discharges are presented

  13. Investigation of the Neutral Gas Pressure Effect on the Metal Resistive Bolometer

    Science.gov (United States)

    Zhang, D.; Giannone, L.; Grulke, O.; Piechotka, M.; Windisch, T.; Stark, A.; Klinger, T.

    2008-03-01

    The bolometer system planned for W7-X consists mainly of metal (Au) resistive detector arrays. All the detectors are exposed to neutral gas environment. The thin bolometer foil used for detecting the radiated power loss may be sensitive to the neutral gas pressure due to the strain gauge effect. Recently, a prototype of this kind of bolometer camera consisting of 12 channels has been installed on the cylindrical plasma device VINETA in order to investigate the influences of the neutral gas pressure on the bolometer signals. Experiments are carried out for Ar-discharges under different gas pressure conditions. It is found that the pressure effect of the neutral gas can make considerable contributions, thus inducing non-negligible errors of the results in most of the investigated cases. Using the VINETA plasmas (Ar, Te<10 eV, ne<10-19 m-3) as examples, the paper demonstrates and discusses how to minimize the neutral gas effects, especially in the data analysis process. The radiated power and the radiation intensity profile obtained in helicon discharges are presented.

  14. Performance of the TFTR bolometers

    International Nuclear Information System (INIS)

    Schivell, J.

    1985-01-01

    For the past year we have been making use of a horizontally viewing 19-channel array and a bolometer which views a narrow cross-sectional slice of the plasma. More recently, we have also obtained results from a second, vertically viewing array. Software has been developed to translate the data from general plasma and array locations to plasma minor radius and to do the Abel inversion with an antisymmetrical term included. Experience has been obtained on the noise and response-time characteristics, as well as the accuracy of total radiated power and radial profiles. Representative cases of radiated power profiles and local power balance are presented, as well as comparisons with other measurements of impurity concentration and trends with electron density and limiter coating. Although most of the ohmic-heating input power leaves by radiation, most of this loss occurs near the outer part of the plasma. Also, the behavior of power profiles during neutral beam injection and disruptions is discussed briefly

  15. Measurements of the Optical Performance of Prototype TES Bolometers for SAFARI

    NARCIS (Netherlands)

    Audley, M. D.; de Lange, G.; Ranjan, M.; Gao, J.-R.; Khosropanah, P.; Ridder, M. L.; Mauskopf, P. D.; Morozov, D.; Doherty, S.; Trappe, N.; Withington, S.

    2014-01-01

    We have measured the optical response of prototype detectors for SAFARI, the far-infrared imaging spectrometer for the SPICA satellite. SAFARI's three bolometer arrays, coupled with a Fourier transform spectrometer, will provide images of a 2'×2' field of view with spectral information over the

  16. FTU bolometer electronic system upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Pollastrone, Fabio, E-mail: fabio.pollastrone@enea.it [Associazione EURATOM-ENEA sulla Fusione, Via Enrico Fermi 45, 00044 Frascati, Rome (Italy); Neri, Carlo; Florean, Marco; Ciccone, Giovanni [Associazione EURATOM-ENEA sulla Fusione, Via Enrico Fermi 45, 00044 Frascati, Rome (Italy)

    2013-10-15

    Highlights: ► Design and realization of a new bolometer electronic system. ► Many improvements over the actual commercial system. ► Architecture based on digital electronic hardware with minimal analog front end. ► Auto off-set correction, real time visualization features and small system size. ► Test results for the electronic system. -- Abstract: The FTU (Frascati Tokamak Upgrade) requires a bolometer diagnostic in order to measure the total plasma radiation. The current diagnostic architecture is based on a full analog multichannel AC bolometer system, which uses a carrier frequency amplifier with a synchronous demodulation. Taking into account the technological upgrades in the field of electronics, it was decided to realize an upgrade for the bolometric electronic system by using a hybrid analog/digital implementation. The new system developed at the ENEA Frascati laboratories has many improvements, and mainly a massive system volume reduction, a good measurement linearity and a simplified use. The new hardware system consists of two subsystems: the Bolometer Digital Control and the Bolometer Analog System. The Bolometer Digital Control can control 16 bolometer bridges through the Bolometer Analog System. The Bolometer Digital Control, based on the FPGA architecture, is connected via Ethernet with a PC; therefore, it can receive commands settings from the PC and send the stream of bolometric measurements in real time to the PC. In order to solve the cross-talk between the bridges and the cables, each of the four bridges in the bolometer head receives a different synthesized excitation frequency. Since the system is fully controlled by a PC GUI (Graphic User Interface), it is very user friendly. Moreover, some useful features have been developed, such as: auto off-set correction, bridge amplitude regulation, software gain setting, real time visualization, frequency excitation selection and noise spectrum analyzer embedded function. In this paper, the

  17. Investigation of CeO2 Buffer Layer Effects on the Voltage Response of YBCO Transition-Edge Bolometers

    DEFF Research Database (Denmark)

    Mohajeri, Roya; Nazifi, Rana; Wulff, Anders Christian

    2016-01-01

    The effect on the thermal parameters of superconducting transition-edge bolometers produced on a single crystalline SrTiO3 (STO) substrate with and without a CeO2 buffer layer was investigated. Metal-organic deposition was used to deposit the 20-nm CeO2 buffer layer, whereas RF magnetron sputtering...

  18. Superconducting properties of Pb82Bi18 films controlled by ferromagnetic nanowire arrays

    International Nuclear Information System (INIS)

    Ye Zuxin; Lyuksyutov, Igor F; Wu Wenhao; Naugle, Donald G

    2011-01-01

    The superconducting properties of Pb 82 Bi 18 alloy films deposited on ferromagnetic nanowire arrays have been investigated. Ferromagnetic Co or Ni nanowires are first electroplated into the columnar pores of anodic aluminum oxide (AAO) membranes. Superconducting Pb 82 Bi 18 films are then quench condensed onto the polished surface of the AAO membranes filled with magnetic nanowires. A strong dependence of the Pb 82 Bi 18 superconducting properties on the ratio of the superconducting film thickness to the magnetic nanowire diameter and material variety was observed.

  19. Superconducting properties of Pb82Bi18 films controlled by ferromagnetic nanowire arrays

    Science.gov (United States)

    Ye, Zuxin; Lyuksyutov, Igor F.; Wu, Wenhao; Naugle, Donald G.

    2011-02-01

    The superconducting properties of Pb82Bi18 alloy films deposited on ferromagnetic nanowire arrays have been investigated. Ferromagnetic Co or Ni nanowires are first electroplated into the columnar pores of anodic aluminum oxide (AAO) membranes. Superconducting Pb82Bi18 films are then quench condensed onto the polished surface of the AAO membranes filled with magnetic nanowires. A strong dependence of the Pb82Bi18 superconducting properties on the ratio of the superconducting film thickness to the magnetic nanowire diameter and material variety was observed.

  20. Hierarchical sinuous-antenna phased array for millimeter wavelengths

    Science.gov (United States)

    Cukierman, Ari; Lee, Adrian T.; Raum, Christopher; Suzuki, Aritoki; Westbrook, Benjamin

    2018-03-01

    We present the design, fabrication, and measured performance of a hierarchical sinuous-antenna phased array coupled to superconducting transition-edge-sensor (TES) bolometers for millimeter wavelengths. The architecture allows for dual-polarization wideband sensitivity with a beam width that is approximately frequency-independent. We report on measurements of a prototype device, which uses three levels of triangular phased arrays to synthesize beams that are approximately constant in width across three frequency bands covering a 3:1 bandwidth. The array element is a lens-coupled sinuous antenna. The device consists of an array of hemispherical lenses coupled to a lithographed wafer, which integrates TESs, planar sinuous antennas, and microwave circuitry including band-defining filters. The approximately frequency-independent beam widths improve coupling to telescope optics and keep the sensitivity of an experiment close to optimal across a broad frequency range. The design can be straightforwardly modified for use with non-TES lithographed cryogenic detectors such as kinetic inductance detectors. Additionally, we report on the design and measurements of a broadband 180° hybrid that can simplify the design of future multichroic focal planes including but not limited to hierarchical phased arrays.

  1. Bolometer electronics

    International Nuclear Information System (INIS)

    Groenig, D.E.

    1981-01-01

    High quality is required to the electronic which works with bolometer made of metal for measuring the radiation power in plasmaphysical experiments. If the bandwidth is to be 1 kHz, and the time constant of the bolometer is about 160 ms by high overall gain the critical parameters are the noise of the amplifier, pick up to the system, stability and decoupling of common mode signals. The high overall gain is necessary to be able to measure lowest radiation power. The design made is a good approach to the desired property. (orig.) [de

  2. Strong Electron Self-Cooling in the Cold-Electron Bolometers Designed for CMB Measurements

    Science.gov (United States)

    Kuzmin, L. S.; Pankratov, A. L.; Gordeeva, A. V.; Zbrozhek, V. O.; Revin, L. S.; Shamporov, V. A.; Masi, S.; de Bernardis, P.

    2018-03-01

    We have realized cold-electron bolometers (CEB) with direct electron self-cooling of the nanoabsorber by SIN (Superconductor-Insulator-Normal metal) tunnel junctions. This electron self-cooling acts as a strong negative electrothermal feedback, improving noise and dynamic properties. Due to this cooling the photon-noise-limited operation of CEBs was realized in array of bolometers developed for the 345 GHz channel of the OLIMPO Balloon Telescope in the power range from 10 pW to 20 pW at phonon temperature Tph =310 mK. The negative electrothermal feedback in CEB is analogous to TES but instead of artificial heating we use cooling of the absorber. The high efficiency of the electron self-cooling to Te =100 mK without power load and to Te=160 mK under power load is achieved by: - a very small volume of the nanoabsorber (0.02 μm3) and a large area of the SIN tunnel junctions, - effective removal of hot quasiparticles by arranging double stock at both sides of the junctions and close position of the normal metal traps, - self-protection of the 2D array of CEBs against interferences by dividing them between N series CEBs (for voltage interferences) and M parallel CEBs (for current interferences), - suppression of Andreev reflection by a thin layer of Fe in the AlFe absorber. As a result even under high power load the CEBs are working at electron temperature Te less than Tph . To our knowledge, there is no analogue in the bolometers technology in the world for bolometers working at electron temperature colder than phonon temperature.

  3. Improved fabrication techniques for infrared bolometers

    Science.gov (United States)

    Lange, A. E.; Mcbride, S. E.; Richards, P. L.; Haller, E. E.; Kreysa, E.

    1983-01-01

    Ion implantation and sputter metallization are used to produce ohmic electrical contacts to Ge:Ga chips. The method is shown to give a high yield of small monolithic bolometers with very little low-frequency noise. It is noted that when one of the chips is used as the thermometric element of a composite bolometer it must be bonded to a dielectric substrate. The thermal resistance of the conventional epoxy bond is measured and found to be undesirably large. A procedure for soldering the chip to a metallized portion of the substrate in such a way as to reduce this resistance is outlined. An evaluation is made of the contribution of the metal film absorber to the heat capacity of a composite bolometer. It is found that the heat capacity of a NiCr absorber at 1.3 K can dominate the bolometer performance. A Bi absorber possesses significantly lower heat capacity. A low-temperature blackbody calibrator is built to measure the optical responsivity of bolometers. A composite bolometer system with a throughput of approximately 0.1 sr sq cm is constructed using the new techniques. The noise in this bolometer is white above 2.5 Hz and is slightly below the value predicted by thermodynamic equilibrium theory.

  4. A millisecond-risetime sub-millimeter light source for lab and in flight bolometer calibration

    Science.gov (United States)

    Abbon, Ph.; Delbart, A.; Fesquet, M.; Magneville, C.; Mazeau, B.; Pansart, J.-P.; Yvon, D.; Dumoulin, L.; Marnieros, S.; Camus, Ph.; Durand, T.; Hoffmann, Ch.

    2007-06-01

    The Olimpo balloon project will use a 120 bolometer camera to observe the sky at four frequencies (143, 217, 385 and 600 GHz) with a resolution of 3 to 2 arc-minute. This paper presents the sub-millimeter calibration "lamp" developed for ground testing and in-flight secondary calibration of bolometric detectors. By design, main features of the device are reproducibility and stability of light flux and millisecond rise time. The radiative device will be placed inside the bolometer camera and will illuminate the bolometer array through a hole in the last 2 K mirror. Operation, readout, and monitoring of the device is ensured by warm electronics. Light output flux and duration is programmable, triggered and monitored from a simple computer RS232 interface. It was tested to be reliable in ballooning temperature conditions from -80 to 50C. Design and test's results are explained.

  5. Crosstalk in a KID Array Caused by the Thickness Variation of Superconducting Metal

    Science.gov (United States)

    Adane, A.; Boucher, C.; Coiffard, G.; Leclercq, S.; Schuster, K. F.; Goupy, J.; Calvo, M.; Hoarau, C.; Monfardini, A.

    2016-07-01

    The work presented in this paper is focused on the improvement of the kinetic detectors used on NIKA2 instrument (New IRAM KID array 2). Based on the simulation and low temperature measurements, it aims at showing how the variations of the superconducting metal corrupt the frequency comb of the kinetic Inductance detectors (KID) in the frequency range (between 1 and 3 GHz), i.e., how the superconducting metal inhomogeneity induces the resonance-to-resonance cross-coupling which deteriorates the homogeneity of the resonance quality factor and the frequency resonance separation. Solutions are then proposed to fight against the effect of these metallic variations when designing the KID array.

  6. Superconducting-normal phase boundary of quasicrystalline arrays in a magnetic field

    International Nuclear Information System (INIS)

    Nori, F.; Niu, Q.; Fradkin, E.; Chang, S.

    1987-01-01

    We study the effect of frustration, induced by a mangnetic field, on the superconducting diamagnetic properties of two-dimensional quasicrystalline arrays. In particular, we calculate the superconducting-normal phase boundary, T/sub c/(H), for several geometries with quasicrystalline order. The agreement between our theoretically obtained phase boundaries and the experimentally obtained ones is very good. We also propose a new way of analytically analyzing the overall and the fine structure of T/sub c/(H) in terms of short- and long-range correlations among tiles

  7. Fast Resistive Bolometer

    International Nuclear Information System (INIS)

    Deeney, C.; Fehl, D.L.; Hanson, D.L.; Keltner, N.R.; McGurn, J.S.; McKenney, J.L.; Spielman, R.B.

    1999-01-01

    Resistive bolometry is an accurate, robust, spectrally broadband technique for measuring absolute x-ray fluence and flux. Bolometry is an independent technique for x-ray measurements that is based on a different set of physical properties than other diagnostics such as x-ray diodes, photoconducting detectors, and P-I-N diodes. Bolometers use the temperature-driven change in element resistivity to determine the total deposited energy. The calibration of such a device is based on fundamental material properties and its physical dimensions. We describe the use of nickel and gold bolometers to measure x rays generated by high-power z pinches on Sandia's Saturn and Z accelerators. The Sandia bolometer design described herein has a pulse response of ∼1 ns. We describe in detail the fabrication, fielding, and data analysis issues leading to highly accurate x-ray measurements. The fundamental accuracy of resistive bolometry will be discussed

  8. Large-format 17μm high-end VOx μ-bolometer infrared detector

    Science.gov (United States)

    Mizrahi, U.; Argaman, N.; Elkind, S.; Giladi, A.; Hirsh, Y.; Labilov, M.; Pivnik, I.; Shiloah, N.; Singer, M.; Tuito, A.; Ben-Ezra, M.; Shtrichman, I.

    2013-06-01

    Long range sights and targeting systems require a combination of high spatial resolution, low temporal NETD, and wide field of view. For practical electro-optical systems it is hard to support these constraints simultaneously. Moreover, achieving these needs with the relatively low-cost Uncooled μ-Bolometer technology is a major challenge in the design and implementation of both the bolometer pixel and the Readout Integrated Circuit (ROIC). In this work we present measured results from a new, large format (1024×768) detector array, with 17μm pitch. This detector meets the demands of a typical armored vehicle sight with its high resolution and large format, together with low NETD of better than 35mK (at F/1, 30Hz). We estimate a Recognition Range for a NATO target of better than 4 km at all relevant atmospheric conditions, which is better than standard 2nd generation scanning array cooled detector. A new design of the detector package enables improved stability of the Non-Uniformity Correction (NUC) to environmental temperature drifts.

  9. An FPGA-based bolometer for the MAST-U Super-X divertor

    Energy Technology Data Exchange (ETDEWEB)

    Lovell, Jack, E-mail: jack.lovell@durham.ac.uk [Durham University, South Road, Durham DH1 3LE (United Kingdom); Culham Centre for Fusion Energy, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Naylor, Graham; Field, Anthony [Culham Centre for Fusion Energy, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Drewelow, Peter [MPI für Plasmaphysik, Greifswald (Germany); Sharples, Ray [Durham University, South Road, Durham DH1 3LE (United Kingdom); Collaboration: EUROfusion Consortium, JET, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)

    2016-11-15

    A new resistive bolometer system has been developed for MAST-Upgrade. It will measure radiated power in the new Super-X divertor, with millisecond time resolution, along 16 vertical and 16 horizontal lines of sight. The system uses a Xilinx Zynq-7000 series Field-Programmable Gate Array (FPGA) in the D-TACQ ACQ2106 carrier to perform real time data acquisition and signal processing. The FPGA enables AC-synchronous detection using high performance digital filtering to achieve a high signal-to-noise ratio and will be able to output processed data in real time with millisecond latency. The system has been installed on 8 previously unused channels of the JET vertical bolometer system. Initial results suggest good agreement with data from existing vertical channels but with higher bandwidth and signal-to-noise ratio.

  10. Bolometer Simulation Using SPICE

    Science.gov (United States)

    Jones, Hollis H.; Aslam, Shahid; Lakew, Brook

    2004-01-01

    A general model is presented that assimilates the thermal and electrical properties of the bolometer - this block model demonstrates the Electro-Thermal Feedback (ETF) effect on the bolometers performance. This methodology is used to construct a SPICE model that by way of analogy combines the thermal and electrical phenomena into one simulation session. The resulting circuit diagram is presented and discussed.

  11. Resistive transition in two-dimensional array of proximity-coupled superconducting weak links

    International Nuclear Information System (INIS)

    Gao Peng; Yu Zheng; Wei Wang; Yao Xi-xian

    1988-01-01

    The Kosterlitz Thouless transition in two-dimensional arrays of proximity-coupled superconducting weak links has been studied in this paper. The samples were prepared by application of the vacuum-evaporation/photoengraving/chemical-etching technique. The experimental results of measurements on some samples of array film showed the existence of the K-T transition in these samples and were consistent with the theory of Lobb, Abraham, and Tinkham

  12. Frequency selective bolometers

    DEFF Research Database (Denmark)

    Kowitt, M.S.; Fixsen, D.J.; Goldin, A.

    1996-01-01

    We propose a concept for radiometry in the millimeter, the submillimeter, and the far-IR spectral regions, the frequency selective bolometer (FSB). This system uses a bolometer as a coupled element of a tuned quasi-optical interference filter in which the absorption, the transmission......-dimensional transmission-line model. Instruments based on FSB technology should have several advantages over current multiband bolometric radiometers including smaller and more compact cryogenic optics; reduced demands on cryostat size and weight, high coupling efficiency, minimum constraints on the geometry in the focal...

  13. Enhancements to a Superconducting Quantum Interference Device (SQUID) Multiplexer Readout and Control System

    Science.gov (United States)

    Forgione, J.; Benford, D. J.; Buchanan, E. D.; Moseley, S. H.; Rebar, J.; Shafer, R. A.

    2004-01-01

    Far-infrared detector arrays such as the 16x32 superconducting bolometer array for the SAFIRE instrument (flying on the SOFIA airborne observatory) require systems of readout and control electronics to provide translation between a user-driven, digital PC and the cold, analog world of the cryogenic detector. In 2001, the National Institute of Standards and Technology (NIST) developed their Mark III electronics for purposes of control and readout of their 1x32 SQUID Multiplexer chips. We at NASA s Goddard Space Flight Center acquired a Mark 111 system and subsequently designed upgrades to suit our and our collaborators purposes. We developed an arbitrary, programmable multiplexing system that allows the user to cycle through rows in a SQUID array in an infinite number of combinations. We provided hooks in the Mark III system to allow readout of signals from outside the Mark 111 system, such as telescope status information. Finally, we augmented the heart of the system with a new feedback algorithm implementation, flexible diagnostic tools, and informative telemetry.

  14. Devil's staircase in a fully frustrated superconducting array

    International Nuclear Information System (INIS)

    Kim, S.; Choi, M.Y.

    1993-01-01

    A two-dimensional fully frustrated superconducting array with a combined direct and alternating applied current is studied both analytically and numerically. At zero temperature equations of motion can be reduced through the use of the translational symmetry present in the system. Remarkably, we find a series of subharmonic steps in addition to standard integer and half-integer giant Shapiro steps, leading to devil's staircase structure. We also present results of detailed numerical simulations, which indeed reveal such subharmonic fine structure. (orig.)

  15. YBCO hot-electron bolometers dedicated to THz detection and imaging: Embedding issues

    International Nuclear Information System (INIS)

    Aurino, M; Tuerer, I; Martinez, A; Gensbittel, A; Degardin, A F; Kreisler, A J

    2010-01-01

    High-T c hot-electron bolometers (HEB) are an interesting alternative to other superconducting heterodyne mixers in the terahertz frequency range because of low-cost cooling investment, ultra-wide instantaneous bandwidth and low intrinsic noise level, even at 80 K. A technological process to fabricate stacked yttrium-based (YBCO) / praseodymium-based (PBCO) ultra-thin films (in the 15 to 40 nm thickness range) etched to form 0.5 μm x 0.5 μm constrictions, elaborated on (100) MgO substrates, has been previously described. Ageing effects were also considered, with the consequence of increased electrical resistance, significant degradation of the regular THz response and no HEB mixing action. Electron and UV lithography steps are revisited here to realize HEB mixers based on nano-bridges covered by a log-periodic planar gold antenna, dedicated to the 1 to 7 THz range. Several measures have been attempted to reduce the conversion losses, mainly by considering the embedding issues related to the YBCO nano-bridge impedance matching to the antenna and the design of optimized intermediate frequency circuitry. Antenna simulations were performed and validated through experiments on scaled models at GHz frequencies. Electromagnetic coupling to the incoming radiation was also studied, including crosstalk between neighbour antennas forming a linear imaging array.

  16. Thermoelectrical-electrothermal feedback (te-et f) enhanced performance characteristics of a high temperature superconductor far-infrared bolometer

    International Nuclear Information System (INIS)

    Kaila, M.M.; Russell, G.J.

    2000-01-01

    Full text: It is more than a decade since the discovery of new a High Temperature Superconducting (HTSC) materials. Their adaptation to large scale applications e.g. high magnetic fields, friction-less motors, levitation trains etc., is still long way to go. Small scale applications e.g., far-infrared sensors, has certainly been established as a highly suitable area for immediate economically viable commercial exploitation. The semiconductor counterparts, NT(Neutron Transmutation doped)Ge, CD(Compensation Doped)Si sensors are not only expensive and difficult to manufacture but also require liquid helium refrigeration at mK temperatures to operate. Although the work around the world has centered on photo-electrical bolometers, in our approach we have adopted a much simpler, temperature stable and a better performing photo-thermoelectrical mode of operation. It is well known that the semi-metal BiSb has the highest electronic thermoelectric figure of merit at liquid nitrogen temperatures. One can obtain a value around 1x10 -2 / K by application of a magnetic field to the BiSb leg of a composite. BiSb-HTSC bolometer. We can use this high figure of merit to our advantage in two different modes of operation of the detector. One is the static mode where the thermoelectric power generated across the semi-metal leg (connected in parallel with the HTSC leg) of the bolometer drives the external electronic circuitry. This circuitry can be remotely (no direct electrical contact) coupled to the bolometer e.g. through the primary coil of a SQUID current amplifier, which can be connected in series with the bolometer inside the cryostat, for better noise performance, or outside, for convenience. Second is the heterodyne operation. The external bias is applied in a constant voltage bias mode. The direction of the bias is so chosen that the transient Peltier power generated, from the incident radiation, in the circuit extracts additional heat at the sensitive area of the bolometer

  17. Low-Noise Wide Bandwith, Hot Electron Bolometer Mixers for Submillimeter Wavelengths

    Science.gov (United States)

    McGrath, W. R.

    1995-01-01

    Recently a novel superconductive hot-electron micro-bolometer has been proposed which is both fast and sensitive (D. E. Prober, Appl. Phys. Lett. 62, 2119, 1993). This device has several important properties which make it useful as a heterodyne sensor for radioastronomy applications at frequencies above 1 THz. The thermal response time of the device is fast enough, several 10's of picoseconds, to allow for IF's of several GHz. This bolometer mixer should operate well up to at least 10 THz. There is no energy gap limitation as in an SIS mixer, since the mixing process relies on heating of the electron gas. In fact, rf power is absorbed more uniformly above the gap frequency. The mixer noise should be near quantum-limited, and the local oscillator (LO) power requirement is very low: / 10 nW for a Nb device. One of the unique features of this device is that it employs rapid electron diffusion into a normal metal, rather than phonon emission, as the thermal conductance that cools the heated electrons. In order for diffusion to dominate over phonon emission, the device must be short, less than 0.5.

  18. Frequency selective bolometer development at Argonne National Laboratory

    Science.gov (United States)

    Datesman, Aaron; Pearson, John; Wang, Gensheng; Yefremenko, Volodymyr; Divan, Ralu; Downes, Thomas; Chang, Clarence; McMahon, Jeff; Meyer, Stephan; Carlstrom, John; Logan, Daniel; Perera, Thushara; Wilson, Grant; Novosad, Valentyn

    2008-07-01

    We discuss the development, at Argonne National Laboratory, of a four-pixel camera suitable for photometry of distant dusty galaxies located by Spitzer and SCUBA, and for study of other millimeter-wave sources such as ultra-luminous infrared galaxies, the Sunyaev-Zeldovich (SZ) effect in clusters, and galactic dust. Utilizing Frequency Selective Bolometers (FSBs) with superconducting Transition-Edge Sensors (TESs), each of the camera's four pixels is sensitive to four colors, with frequency bands centered approximately at 150, 220, 270, and 360 GHz. The current generation of these devices utilizes proximity effect superconducting bilayers of Mo/Au or Ti/Au for TESs, along with frequency selective circuitry on membranes of silicon nitride 1 cm across and 1 micron thick. The operational properties of these devices are determined by this circuitry, along with thermal control structures etched into the membranes. These etched structures do not perforate the membrane, so that the device is both comparatively robust mechanically and carefully tailored in terms of its thermal transport properties. In this paper, we report on development of the superconducting bilayer TES technology and characterization of the FSB stacks. This includes the use of new materials, the design and testing of thermal control structures, the introduction of desirable thermal properties using buried layers of crystalline silicon underneath the membrane, detector stability control, and optical and thermal test results. The scientific motivation, FSB design, FSB fabrication, and measurement results are discussed.

  19. Measurements of the Optical Performance of Prototype TES Bolometers for SAFARI

    Science.gov (United States)

    Audley, M. D.; de Lange, G.; Ranjan, M.; Gao, J.-R.; Khosropanah, P.; Ridder, M. L.; Mauskopf, P. D.; Morozov, D.; Doherty, S.; Trappe, N.; Withington, S.

    2014-09-01

    We have measured the optical response of prototype detectors for SAFARI, the far-infrared imaging spectrometer for the SPICA satellite. SAFARI's three bolometer arrays, coupled with a Fourier transform spectrometer, will provide images of a 2'×2' field of view with spectral information over the wavelength range 34-210 μm. Each horn-coupled bolometer consists of a transition edge sensor (TES), with a transition temperature close to 100 mK, and a thin-film Ta absorber on a thermally-isolated silicon nitride membrane. SAFARI requires extremely sensitive detectors ( NEP˜2×10-19 W/), with correspondingly low saturation powers (˜5 fW), to take advantage of SPICA's cooled optics. To meet the challenge of testing such sensitive detectors we have constructed an ultra-low background test facility based on a cryogen-free high-capacity dilution refrigerator, paying careful attention to stray-light exclusion, shielding, and vibration isolation. For optical measurements the system contains internal cold (3-30 K) and hot (˜300 K) black-body calibration sources, as well as a light pipe for external illumination. We discuss our measurements of high optical efficiency in prototype SAFARI detectors and describe recent improvements to the test facility that will enable us to test the full SAFARI focal-plane arrays.

  20. Subharmonic structure of Shapiro steps in frustrated superconducting arrays

    International Nuclear Information System (INIS)

    Kim, S.; Kim, B.J.; Choi, M.Y.

    1995-01-01

    Two-dimensional superconducting arrays with combined direct and alternating applied currents are studied both analytically and numerically. In particular, we investigate in detail current-voltage characteristics of a square array with 1/2 flux quantum per plaquette and triangular arrays with 1/2 and 1/4 flux quantum per plaquette. At zero temperature reduced equations of motion are obtained through the use of the translational symmetry present in the systems. The reduced equations lead to a series of subharmonic steps in addition to the standard integer and fractional giant Shapiro steps, producing devil's staircase structure. This devil's staircase structure reflects the existence of dynamically generated states in addition to the states originating from degenerate ground states in equilibrium. Widths of the subharmonic steps as functions of the amplitudes of alternating currents display Bessel-function-type behavior. We also present results of extensive numerical simulations, which indeed reveal the subharmonic steps together with their stability against small thermal fluctuations. Implications for topological invariance are also discussed

  1. Superconductivity applications for infrared and microwave devices II; Proceedings of the Meeting, Orlando, FL, Apr. 4, 5, 1991

    Science.gov (United States)

    Heinen, Vernon O.; Bhasin, Kul B.

    Topics discussed include thin-film technology, microwave transmission lines and resonators, microwave devices and circuits, infrared detectors and bolometers, and superconducting junctions. Papers are presented on possible enhancement in bolometric response using free-standing film of YBa2Cu3O(x), aging and surface instability in high-Tc superconductors, epitaxial Tl2Ba2CaCu2O8 thin films on LaAlO3 and their microwave device properties, the performance of stripline resonators using sputtered YBCO films, and a coplanar waveguide microwave filter of YBa2Cu3O7. Attention is also given to the performance characteristics of Y-Ba-Cu-O microwave superconducting detectors, high-Tc bolometer developments for planetary missions, infrared detectors from YBaCuO thin films, high-temperature superconductor junction technology, and submillimeter receiver components using superconducting tunnel junctions. (For individual items see A93-27244 to A93-27248)

  2. Fabrication of Antenna-Coupled KID Array for Cosmic Microwave Background Detection

    Science.gov (United States)

    Tang, Q. Y.; Barry, P. S.; Basu Thakur, R.; Kofman, A.; Nadolski, A.; Vieira, J.; Shirokoff, E.

    2018-05-01

    Kinetic inductance detectors (KIDs) have become an attractive alternative to traditional bolometers in the sub-mm and mm observing community due to their innate frequency multiplexing capabilities and simple lithographic processes. These advantages make KIDs a viable option for the O(500,000) detectors needed for the upcoming Cosmic Microwave Background-Stage 4 experiment. We have fabricated an antenna-coupled MKID array in the 150 GHz band optimized for CMB detection. Our design uses a twin-slot antenna coupled to an inverted microstrip made from a superconducting Nb/Al bilayer as the strip, a Nb ground plane and a SiN_x dielectric layer in between, which is then coupled to an Al KID grown on high-resistivity Si. We present the fabrication process and measurements of SiN_x microstrip resonators.

  3. Broadband sample holder for microwave spectroscopy of superconducting qubits

    International Nuclear Information System (INIS)

    Averkin, A. S.; Karpov, A.; Glushkov, E.; Abramov, N.; Shulga, K.; Huebner, U.; Il'ichev, E.; Ustinov, A. V.

    2014-01-01

    We present a practical design and implementation of a broadband sample holder suitable for microwave experiments with superconducting integrated circuits at millikelvin temperatures. Proposed design can be easily integrated in standard dilution cryostats, has flat pass band response in a frequency range from 0 to 32 GHz, allowing the RF testing of the samples with substrate size up to 4 × 4 mm 2 . The parasitic higher modes interference in the holder structure is analyzed and prevented via design considerations. The developed setup can be used for characterization of superconducting parametric amplifiers, bolometers, and qubits. We tested the designed sample holder by characterizing of a superconducting flux qubit at 20 mK temperature

  4. Vortex pinning vs superconducting wire network: origin of periodic oscillations induced by applied magnetic fields in superconducting films with arrays of nanomagnets

    International Nuclear Information System (INIS)

    Gomez, A; Del Valle, J; Gonzalez, E M; Vicent, J L; Chiliotte, C E; Carreira, S J; Bekeris, V; Prieto, J L; Schuller, Ivan K

    2014-01-01

    Hybrid magnetic arrays embedded in superconducting films are ideal systems to study the competition between different physical (such as the coherence length) and structural length scales such as are available in artificially produced structures. This interplay leads to oscillation in many magnetically dependent superconducting properties such as the critical currents, resistivity and magnetization. These effects are generally analyzed using two distinct models based on vortex pinning or wire network. In this work, we show that for magnetic dot arrays, as opposed to antidot (i.e. holes) arrays, vortex pinning is the main mechanism for field induced oscillations in resistance R(H), critical current I c (H), magnetization M(H) and ac-susceptibility χ ac (H) in a broad temperature range. Due to the coherence length divergence at T c , a crossover to wire network behaviour is experimentally found. While pinning occurs in a wide temperature range up to T c , wire network behaviour is only present in a very narrow temperature window close to T c . In this temperature interval, contributions from both mechanisms are operational but can be experimentally distinguished. (papers)

  5. A superconducting quadrupole array for transport of multiple high current beams

    International Nuclear Information System (INIS)

    Faltens, A.; Shuman, D.

    1999-01-01

    We present a conceptual design of a superconducting quadrupole magnet array for the side-by-side transport of multiple high current particle beams in induction linear accelerators. The magnetic design uses a modified cosine 20 current distribution inside a square cell boundary. Each interior magnet's neighbors serve as the return flux paths and the poles are placed as close as possible to each other to facilitate this. No iron is present in the basic 2-D magnetic design; it will work at any current level without correction windings. Special 1/8th quadrupoles are used along the transverse periphery of the array to contain and channel flux back into the array, making every channel look as part of an infinite array. This design provides a fixed dimension array boundary equal to the quadrupole radius that can be used for arrays of any number of quadrupole channels, at any field level. More importantly, the design provides magnetic field separation between the array and the induction cores which may be surrounding it. Flux linkage between these two components can seriously affect the operation of both of them

  6. Arrays of Cooper pair boxes coupled to a superconducting reservoir: 'superradiance' and 'revival'

    International Nuclear Information System (INIS)

    Rodrigues, D A; Gyoerffy, B L; Spiller, T P

    2004-01-01

    We consider an array of l b Cooper pair boxes, each of which is coupled to a superconducting reservoir by a capacitive tunnel junction. We discuss two effects that probe not just the quantum nature of the islands, but also of the superconducting reservoir coupled to them. These are analogues to the well-known quantum optical effects 'superradiance' and 'revival'. When revival is extended to multiple systems, we find that 'entanglement revival' can also be observed. In order to study the above effects, we utilize a highly simplified model for these systems in which all the single-electron energy eigenvalues are set to be the same (the strong coupling limit), as are the charging energies of the Cooper pair boxes, allowing the whole system to be represented by two coupled quantum spins, one finite, which represents the array of boxes, and one representing the reservoir, which we consider in the limit of infinite size. Although this simplification is drastic, the model retains the main features necessary to capture the phenomena of interest. Given the progress in superconducting box experiments over recent years, it is possible that experiments to investigate both of these interesting quantum coherent phenomena could be performed in the foreseeable future

  7. Neutron Transmutation Doped (NTD) germanium thermistors for sub-mm bolometer applications

    Science.gov (United States)

    Haller, E. E.; Itoh, K. M.; Beeman, J. W.

    1996-01-01

    Recent advances in the development of neutron transmutation doped (NTD) semiconductor thermistors fabricated from natural and controlled isotopic composition germanium are reported. The near ideal doping uniformity that can be achieved with the NTD process, the device simplicity of NTD Ge thermistors and the high performance of cooled junction field effect transistor preamplifiers led to the widespread acceptance of these thermal sensors in ground-based, airborne and spaceborne radio telescopes. These features made possible the development of efficient bolometer arrays.

  8. Monolayer Graphene Bolometer as a Sensitive Far-IR Detector

    Science.gov (United States)

    Karasik, Boris S.; McKitterick, Christopher B.; Prober, Daniel E.

    2014-01-01

    In this paper we give a detailed analysis of the expected sensitivity and operating conditions in the power detection mode of a hot-electron bolometer (HEB) made from a few micro m(sup 2) of monolayer graphene (MLG) flake which can be embedded into either a planar antenna or waveguide circuit via NbN (or NbTiN) superconducting contacts with critical temperature approx. 14 K. Recent data on the strength of the electron-phonon coupling are used in the present analysis and the contribution of the readout noise to the Noise Equivalent Power (NEP) is explicitly computed. The readout scheme utilizes Johnson Noise Thermometry (JNT) allowing for Frequency-Domain Multiplexing (FDM) using narrowband filter coupling of the HEBs. In general, the filter bandwidth and the summing amplifier noise have a significant effect on the overall system sensitivity.

  9. Lateral terahertz hot-electron bolometer based on an array of Sn nanothreads in GaAs

    Science.gov (United States)

    Ponomarev, D. S.; Lavrukhin, D. V.; Yachmenev, A. E.; Khabibullin, R. A.; Semenikhin, I. E.; Vyurkov, V. V.; Ryzhii, M.; Otsuji, T.; Ryzhii, V.

    2018-04-01

    We report on the proposal and the theoretical and experimental studies of the terahertz hot-electron bolometer (THz HEB) based on a gated GaAs structure like the field-effect transistor with the array of parallel Sn nanothreads (Sn-NTs). The operation of the HEB is associated with an increase in the density of the delocalized electrons due to their heating by the incoming THz radiation. The quantum and the classical device models were developed, the quantum one was based on the self-consistent solution of the Poisson and Schrödinger equations, the classical model involved the Poisson equation and density of states omitting quantization. We calculated the electron energy distributions in the channels formed around the Sn-NTs for different gate voltages and found the fraction of the delocalized electrons propagating across the energy barriers between the NTs. Since the fraction of the delocalized electrons strongly depends on the average electron energy (effective temperature), the proposed THz HEB can exhibit an elevated responsivity compared with the HEBs based on more standard heterostructures. Due to a substantial anisotropy of the device structure, the THz HEB may demonstrate a noticeable polarization selectivity of the response to the in-plane polarized THz radiation. The features of the THz HEB might be useful in their practical applications in biology, medicine and material science.

  10. Macroscopic weak superconductivity of an NXN Josephson junction array below the Kosterlitz-Thouless transition

    International Nuclear Information System (INIS)

    Shenoy, S.R.; Karlsruhe Univ.

    1983-07-01

    A two-dimensional NXN array of coupled Josephson junctions, each of size tau 0 and Josephson length lambdasub(JO)>>tau 0 , is shown to exhibit macroscopic weak superconductivity. The Josephson phase coherence here extends across the array, vanishing discontinuously at the Kosterlitz-Thouless transition temperature. The transverse size Ntau 0 must be smaller than a few times the effective Josephson screening length lambdasub(J)sup(eff) proportional to lambdasub(JO), for a sharp transition to be seen. (author)

  11. Low-cost far infrared bolometer camera for automotive use

    Science.gov (United States)

    Vieider, Christian; Wissmar, Stanley; Ericsson, Per; Halldin, Urban; Niklaus, Frank; Stemme, Göran; Källhammer, Jan-Erik; Pettersson, Håkan; Eriksson, Dick; Jakobsen, Henrik; Kvisterøy, Terje; Franks, John; VanNylen, Jan; Vercammen, Hans; VanHulsel, Annick

    2007-04-01

    A new low-cost long-wavelength infrared bolometer camera system is under development. It is designed for use with an automatic vision algorithm system as a sensor to detect vulnerable road users in traffic. Looking 15 m in front of the vehicle it can in case of an unavoidable impact activate a brake assist system or other deployable protection system. To achieve our cost target below €100 for the sensor system we evaluate the required performance and can reduce the sensitivity to 150 mK and pixel resolution to 80 x 30. We address all the main cost drivers as sensor size and production yield along with vacuum packaging, optical components and large volume manufacturing technologies. The detector array is based on a new type of high performance thermistor material. Very thin Si/SiGe single crystal multi-layers are grown epitaxially. Due to the resulting valence barriers a high temperature coefficient of resistance is achieved (3.3%/K). Simultaneously, the high quality crystalline material provides very low 1/f-noise characteristics and uniform material properties. The thermistor material is transferred from the original substrate wafer to the read-out circuit using adhesive wafer bonding and subsequent thinning. Bolometer arrays can then be fabricated using industry standard MEMS process and materials. The inherently good detector performance allows us to reduce the vacuum requirement and we can implement wafer level vacuum packaging technology used in established automotive sensor fabrication. The optical design is reduced to a single lens camera. We develop a low cost molding process using a novel chalcogenide glass (GASIR®3) and integrate anti-reflective and anti-erosion properties using diamond like carbon coating.

  12. Multichroic Antenna-Coupled Bolometers for CMB Polarization and Sub-mm Observations

    Science.gov (United States)

    Lee, Adrian

    We propose to develop planar antenna-coupled superconducting bolometer arrays for observations at sub-millimeter to millimeter wavelengths. Our pixel architecture features a dual-polarization log-periodic antenna with a 4:1-bandwidth ratio, followed by a filter bank that divides the total bandwidth into several broad photometric bands. The advantages of this approach, compared with those using conventional single-color pixels, include a combination of greatly reduced focal-plane mass, higher array sensitivity, and a larger number of spectral bands. These advantages have the potential to greatly reduce the cost and/or increase the performance of NASA missions in the sub-millimeter to millimeter bands. For CMB polarization measurements, a wide frequency range of roughly 30 to 300 GHz is required to subtract galactic foregrounds. The multichroic architecture we propose enables a relatively low-cost 30-cm aperture space mission to have sufficient sensitivity to probe below the tensor-to-scalar ratio r = 0.01. For a larger aperture mission, such as the EPIC-IM concept, the proposed technology could reduce the focal-plane mass by a factor of 2-3, with great savings in required cryocooler performance and therefore cost. We have demonstrated the lens-coupled antenna concept in the POLARBEAR ground-based CMB polarization experiment now operating in Chile. That experiment uses a single-band planar antenna and produces excellent beam properties and optical efficiency. In the laboratory, we have measured two octaves of total bandwidth in the log-periodic sinuous antenna. We have built filter banks of 2, 3, and 7 bands with 4, 6, and 14 bolometers per pixel for two linear polarizations. Building on these accomplishments, the deliverables for the proposed work include: *Two pixel types that together cover the range from 30 to 300 GHz. The low-frequency pixel will have bands centered at 35, 50, and 80 GHz and the high frequency pixel will have bands centered at 120, 180, and 270

  13. High-performance ferroelectric and magnetoresistive materials for next-generation thermal detector arrays

    Science.gov (United States)

    Todd, Michael A.; Donohue, Paul P.; Watton, Rex; Williams, Dennis J.; Anthony, Carl J.; Blamire, Mark G.

    2002-12-01

    This paper discusses the potential thermal imaging performance achievable from thermal detector arrays and concludes that the current generation of thin-film ferroelectric and resistance bolometer based detector arrays are limited by the detector materials used. It is proposed that the next generation of large uncooled focal plane arrays will need to look towards higher performance detector materials - particularly if they aim to approach the fundamental performance limits and compete with cooled photon detector arrays. Two examples of bolometer thin-film materials are described that achieve high performance from operating around phase transitions. The material Lead Scandium Tantalate (PST) has a paraelectric-to-ferroelectric phase transition around room temperature and is used with an applied field in the dielectric bolometer mode for thermal imaging. PST films grown by sputtering and liquid-source CVD have shown merit figures for thermal imaging a factor of 2 to 3 times higher than PZT-based pyroelectric thin films. The material Lanthanum Calcium Manganite (LCMO) has a paramagnetic to ferromagnetic phase transition around -20oC. This paper describes recent measurements of TCR and 1/f noise in pulsed laser-deposited LCMO films on Neodymium Gallate substrates. These results show that LCMO not only has high TCR's - up to 30%/K - but also low 1/f excess noise, with bolometer merit figures at least an order of magnitude higher than Vanadium Oxide, making it ideal for the next generation of microbolometer arrays. These high performance properties come at the expense of processing complexities and novel device designs will need to be introduced to realize the potential of these materials in the next generation of thermal detectors.

  14. Superconducting Quantum Arrays for Wideband Antennas and Low Noise Amplifiers

    Science.gov (United States)

    Mukhanov, O.; Prokopemko, G.; Romanofsky, Robert R.

    2014-01-01

    Superconducting Quantum Iinetference Filters (SQIF) consist of a two-dimensional array of niobium Josephson Junctions formed into N loops of incommensurate area. This structure forms a magnetic field (B) to voltage transducer with an impulse like response at B0. In principle, the signal-to-noise ratio scales as the square root of N and the noise can be made arbitrarily small (i.e. The SQIF chips are expected to exhibit quantum limited noise performance). A gain of about 20 dB was recently demonstrated at 10 GHz.

  15. Development of plasma bolometers using fiber-optic temperature sensors

    Energy Technology Data Exchange (ETDEWEB)

    Reinke, M. L., E-mail: reinkeml@ornl.gov [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Han, M.; Liu, G. [University of Nebraska-Lincoln, Lincoln, Nebraska 68588 (United States); Eden, G. G. van [Dutch Institute for Fundamental Energy Research, De Zaale 20, 5612 AJ Eindhoven (Netherlands); Evenblij, R.; Haverdings, M. [Technobis, Pyrietstraat 2, 1812 SC Alkmaar (Netherlands); Stratton, B. C. [Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States)

    2016-11-15

    Measurements of radiated power in magnetically confined plasmas are important for exhaust studies in present experiments and expected to be a critical diagnostic for future fusion reactors. Resistive bolometer sensors have long been utilized in tokamaks and helical devices but suffer from electromagnetic interference (EMI). Results are shown from initial testing of a new bolometer concept based on fiber-optic temperature sensor technology. A small, 80 μm diameter, 200 μm long silicon pillar attached to the end of a single mode fiber-optic cable acts as a Fabry–Pérot cavity when broadband light, λ{sub o} ∼ 1550 nm, is transmitted along the fiber. Changes in temperature alter the optical path length of the cavity primarily through the thermo-optic effect, resulting in a shift of fringes reflected from the pillar detected using an I-MON 512 OEM spectrometer. While initially designed for use in liquids, this sensor has ideal properties for use as a plasma bolometer: a time constant, in air, of ∼150 ms, strong absorption in the spectral range of plasma emission, immunity to local EMI, and the ability to measure changes in temperature remotely. Its compact design offers unique opportunities for integration into the vacuum environment in places unsuitable for a resistive bolometer. Using a variable focus 5 mW, 405 nm, modulating laser, the signal to noise ratio versus power density of various bolometer technologies are directly compared, estimating the noise equivalent power density (NEPD). Present tests show the fiber-optic bolometer to have NEPD of 5-10 W/m{sup 2} when compared to those of the resistive bolometer which can achieve <0.5 W/m{sup 2} in the laboratory, but this can degrade to 1-2 W/m{sup 2} or worse when installed on a tokamak. Concepts are discussed to improve the signal to noise ratio of this new fiber-optic bolometer by reducing the pillar height and adding thin metallic coatings, along with improving the spectral resolution of the interrogator.

  16. Multi-channel bolometer system on JFT-2M tokamak

    International Nuclear Information System (INIS)

    Tamai, Hiroshi; Maeno, Masaki; Matsuda, Toshiaki; Matoba, Tohru

    1988-07-01

    Multi-channel bolometer system is designed and installed to observe the radiation profile on JFT-2M tokamak. Sensor head is made of Thinistor, which is a kind of semiconductor, because it has the advantage of higher sensitivity of about one order of magnitude than the conventional metal foil bolometer and is suitable for the profile measurement in which the signal from the plasma is relatively small. The response and cooling characteristics of the bolometer sensor are suitable for the condition of JFT-2M tokamak plasma. Low noise circuit of bridge and differentiator is developed to optimize the signal to noise ratio in the JFT-2M operating condition. With use of the bolometer system, the radiation profile in joule heating plasma as well as additional heating plasma especially in H-mode plasma is successfully observed. (author)

  17. Design and fabrication of a bidimentional microbolometer array for Terahertz detection characterized at different temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Orduna-Diaz, A [CIBA-Tlaxcala, IPN, Tlaxcala, Tlax.(Mexico); Castillo-DomInguez, E; Torres-Jacome, A; De la Hidalga-Wade, F J; Trevino-Palacios, C G, E-mail: abdu@inaoep.mx [Instituto Nacional de Astrofisica, Optica y Electronica, Apdo. Postal 51 y 216, Puebla, Pue. 72000 (Mexico)

    2011-01-01

    We present the design, micromachining and characterization of a bidimentional bolometer array for radiation detection in the 0.7-1.5 THz frequency range. The detector is based on a boron doped amorphous silicon film (a-Si-B:H). The film optimized for sensitivity enhancement was obtained using 500 sccm diborane flow with 95 nm thickness. The sensing layer was deposited using plasma enhanced chemical vapor deposition (PECVD) technique at low frequency on a 0.45 {mu}m thick silicon nitride membrane sustained by a micromachined frame in crystalline silicon. The design consists of four 5x5 bolometer arrays made by conventional lithography. The bolometer active area is 660 {mu}m x 420 {mu}m and the detector will operate as a focal plane array. The current-voltage characteristics present an ohmic behaviour; the temperature coefficient of resistance (TCR) was obtained by measuring the bolometer performance from room temperature down to liquid nitrogen temperature. The responsivity was measured under illumination from a black body radiating at 300, 500, 700, 900 and 1100 deg. C, obtaining a value of R =1.17 x 10{sup -2} A/W with a dark current of 4.43 x 10{sup -9} A

  18. A strained silicon cold electron bolometer using Schottky contacts

    Energy Technology Data Exchange (ETDEWEB)

    Brien, T. L. R., E-mail: tom.brien@astro.cf.ac.uk; Ade, P. A. R.; Barry, P. S.; Dunscombe, C.; Morozov, D. V.; Sudiwala, R. V. [School of Physics and Astronomy, Cardiff University, Queen' s Buildings, The Parade, Cardiff CF24 3AA (United Kingdom); Leadley, D. R.; Myronov, M.; Parker, E. H. C.; Prest, M. J.; Whall, T. E. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Prunnila, M. [VTT Technical Research Centre of Finland, P.O. Box 1000, FI-02044 VTT Espoo (Finland); Mauskopf, P. D. [School of Physics and Astronomy, Cardiff University, Queen' s Buildings, The Parade, Cardiff CF24 3AA (United Kingdom); Department of Physics and School of Earth and Space Exploration, Arizona State University, 650 E. Tyler Mall, Tempe, Arizona 85287 (United States)

    2014-07-28

    We describe optical characterisation of a strained silicon cold electron bolometer (CEB), operating on a 350 mK stage, designed for absorption of millimetre-wave radiation. The silicon cold electron bolometer utilises Schottky contacts between a superconductor and an n{sup ++} doped silicon island to detect changes in the temperature of the charge carriers in the silicon, due to variations in absorbed radiation. By using strained silicon as the absorber, we decrease the electron-phonon coupling in the device and increase the responsivity to incoming power. The strained silicon absorber is coupled to a planar aluminium twin-slot antenna designed to couple to 160 GHz and that serves as the superconducting contacts. From the measured optical responsivity and spectral response, we calculate a maximum optical efficiency of 50% for radiation coupled into the device by the planar antenna and an overall noise equivalent power, referred to absorbed optical power, of 1.1×10{sup −16} W Hz{sup −1/2} when the detector is observing a 300 K source through a 4 K throughput limiting aperture. Even though this optical system is not optimized, we measure a system noise equivalent temperature difference of 6 mK Hz{sup −1/2}. We measure the noise of the device using a cross-correlation of time stream data, measured simultaneously with two junction field-effect transistor amplifiers, with a base correlated noise level of 300 pV Hz{sup −1/2} and find that the total noise is consistent with a combination of photon noise, current shot noise, and electron-phonon thermal noise.

  19. Superconductivity applications for infrared and microwave devices; Proceedings of the Meeting, Orlando, FL, Apr. 19, 20, 1990

    Science.gov (United States)

    Bhasin, Kul B.; Heinen, Vernon O.

    1990-10-01

    Various papers on superconductivity applications for IR and microwave devices are presented. The individual topics addressed include: pulsed laser deposition of Tl-Ca-Ba-Cu-O films, patterning of high-Tc superconducting thin films on Si substrates, IR spectra and the energy gap in thin film YBa2Cu3O(7-delta), high-temperature superconducting thin film microwave circuits, novel filter implementation utilizing HTS materials, high-temperature superconductor antenna investigations, high-Tc superconducting IR detectors, high-Tc superconducting IR detectors from Y-Ba-Cu-O thin films, Y-Ba-Cu0-O thin films as high-speed IR detectors, fabrication of a high-Tc superconducting bolometer, transition-edge microbolometer, photoresponse of YBa2Cu3O(7-delta) granular and epitaxial superconducting thin films, fast IR response of YBCO thin films, kinetic inductance effects in high-Tc microstrip circuits at microwave frequencies.

  20. Design of a bolometer for total-energy measurement of the linear coherent light source pulsed X-ray laser

    International Nuclear Information System (INIS)

    Friedrich, S.; Li, L.; Ott, L.L.; Kolgani, Rajeswari M.; Yong, G.J.; Ali, Z.A.; Drury, O.B.; Ables, E.; Bionta, R.M.

    2006-01-01

    We are developing a cryogenic bolometer to measure the total energy of the linear coherent light source (LCLS) free electron X-ray laser to be built at the Stanford Linear Accelerator Center. The laser will produce ultrabright X-ray pulses in the energy range between 0.8 and 8 keV with ∼10 12 photons per ∼200 fs pulse at a repeat interval of 8 ms, and will be accompanied by a halo of spontaneous undulator radiation. The bolometer is designed to determine the total energy of each laser pulse to within (1- x ) Sr x MnO 3 sensor array at the metal-insulator transition, where the composition x is adjusted to produce the desired transition temperature. We discuss design considerations and material choices, and present numerical simulations of the thermal response

  1. Investigation of electrical noise in selenium-immersed thermistor bolometers

    Science.gov (United States)

    Tarpley, J. L.; Sarmiento, P. D.

    1980-01-01

    The selenium immersed, thermistor bolometer, IR detector failed due to spurious and escalating electrical noise outburst as a function of time at elevated temperatures during routine ground based testing in a space simulated environment. Spectrographic analysis of failed bolometers revealed selenium pure zones in the insulating selenium arsenic (Se-As) glass film which surrounds the active sintered Mn, Ni, Co oxide flake. The selenium pure film was identified as a potentially serious failure mechanism. Significant changes were instituted in the manufacturing techniques along with more stringent process controls which eliminated the selenium pure film and successfully produced 22study bolometers.

  2. Observation of high Tc one dimensional superconductivity in 4 angstrom carbon nanotube arrays

    KAUST Repository

    Zhang, Bing; Liu, Yang; Chen, Qihong; Lai, Zhiping; Sheng, Ping

    2017-01-01

    The only known approach to fabricate large, uniform arrays of 4-Å single wall carbon nanotubes (SWNTs) is by using zeolite crystals as the template, in which the nanotubes are formed by chemical vapor deposition inside the linear channels of the AlPO-5 (AFI for short) zeolite. However, up to now the pore filling factor has been very low, as evidenced by the weight percentage of carbon in thermal gravimetric analysis (TGA) measurements. In this work, we show that by using a new, micro-platelet AFI crystals as the template, combined with the use of a new CVD process, we can increase the TGA result to 22.5wt%, which translates to a pore filling factor of 91%. We have observed one dimensional (1D) superconductivity in such samples. The temperature dependence of resistance shows a smooth decreasing trend below 60 K, and the differential resistance displays a gap that disappears above the 1D superconducting initiation temperature. The observed behaviour is shown to agree very well with the theoretical predictions of 1D superconductivity.

  3. Observation of high Tc one dimensional superconductivity in 4 angstrom carbon nanotube arrays

    KAUST Repository

    Zhang, Bing

    2017-02-14

    The only known approach to fabricate large, uniform arrays of 4-Å single wall carbon nanotubes (SWNTs) is by using zeolite crystals as the template, in which the nanotubes are formed by chemical vapor deposition inside the linear channels of the AlPO-5 (AFI for short) zeolite. However, up to now the pore filling factor has been very low, as evidenced by the weight percentage of carbon in thermal gravimetric analysis (TGA) measurements. In this work, we show that by using a new, micro-platelet AFI crystals as the template, combined with the use of a new CVD process, we can increase the TGA result to 22.5wt%, which translates to a pore filling factor of 91%. We have observed one dimensional (1D) superconductivity in such samples. The temperature dependence of resistance shows a smooth decreasing trend below 60 K, and the differential resistance displays a gap that disappears above the 1D superconducting initiation temperature. The observed behaviour is shown to agree very well with the theoretical predictions of 1D superconductivity.

  4. Fabrication of close-packed TES microcalorimeter arrays using superconducting molybdenum/gold transition-edge sensors

    Science.gov (United States)

    Finkbeiner, F. M.; Brekosky, R. P.; Chervenak, J. A.; Figueroa-Feliciano, E.; Li, M. J.; Lindeman, M. A.; Stahle, C. K.; Stahle, C. M.; Tralshawala, N.

    2002-02-01

    We present an overview of our efforts in fabricating Transition-Edge Sensor (TES) microcalorimeter arrays for use in astronomical x-ray spectroscopy. Two distinct types of array schemes are currently pursued: 5×5 single pixel TES array where each pixel is a TES microcalorimeter, and Position-Sensing TES (PoST) array. In the latter, a row of 7 or 15 thermally-linked absorber pixels is read out by two TES at its ends. Both schemes employ superconducting Mo/Au bilayers as the TES. The TES are placed on silicon nitride membranes for thermal isolation from the structural frame. The silicon nitride membranes are prepared by a Deep Reactive Ion Etch (DRIE) process into a silicon wafer. In order to achieve the concept of closely packed arrays without decreasing its structural and functional integrity, we have already developed the technology to fabricate arrays of cantilevered pixel-sized absorbers and slit membranes in silicon nitride films. Furthermore, we have started to investigate ultra-low resistance through-wafer micro-vias to bring the electrical contact out to the back of a wafer. .

  5. Polarization measurements made on LFRA and OASIS emitter arrays

    Science.gov (United States)

    Geske, Jon; Sparkman, Kevin; Oleson, Jim; Laveigne, Joe; Sieglinger, Breck; Marlow, Steve; Lowry, Heard; Burns, James

    2008-04-01

    Polarization is increasingly being considered as a method of discrimination in passive sensing applications. In this paper the degree of polarization of the thermal emission from the emitter arrays of two new Santa Barbara Infrared (SBIR) micro-bolometer resistor array scene projectors was characterized at ambient temperature and at 77 K. The emitter arrays characterized were from the Large Format Resistive Array (LFRA) and the Optimized Arrays for Space-Background Infrared Simulation (OASIS) scene projectors. This paper reports the results of this testing.

  6. Frequency-multiplexed bias and readout of a 16-pixel superconducting nanowire single-photon detector array

    Science.gov (United States)

    Doerner, S.; Kuzmin, A.; Wuensch, S.; Charaev, I.; Boes, F.; Zwick, T.; Siegel, M.

    2017-07-01

    We demonstrate a 16-pixel array of microwave-current driven superconducting nanowire single-photon detectors with an integrated and scalable frequency-division multiplexing architecture, which reduces the required number of bias and readout lines to a single microwave feed line. The electrical behavior of the photon-sensitive nanowires, embedded in a resonant circuit, as well as the optical performance and timing jitter of the single detectors is discussed. Besides the single pixel measurements, we also demonstrate the operation of a 16-pixel array with a temporal, spatial, and photon-number resolution.

  7. The Polarization-Sensitive Bolometers for SPICA and their Potential Use for Ground-Based Application

    Science.gov (United States)

    Reveret, Vincent

    2018-01-01

    CEA is leading the development of Safari-POL, an imaging-polarimeter aboard the SPICA space observatory (ESA M5). SPICA will be able to reach unprecedented sensitivities thanks to its cooled telescope and its ultra-sensitive detectors. The detector assembly of Safari-POL holds three arrays that are cooled down to 50 mK and correspond to three spectral bands : 100, 200 and 350 microns. The detectors (silicon bolometers), benefit from the Herschel/PACS legacy and are also a big step forward in term of sensitivity (improved by two orders of magnitude compared to PACS bolometers) and for polarimetry capabilities. Indeed, each pixel is intrinsically sensitive to two polarization components (Horizontal and Vertical). We will present the Safari-POL concept, the first results of measurements made on the detectors, and future plans for possible ground-based instruments using this technology. We will also present the example of the ArTéMiS camera, installed at APEX, that was developped as a ground-based conterpart of the PACS photometer.

  8. The LUCIFER/CUPID-0 demonstrator: searching for the neutrinoless double-beta decay with Zn82Se scintillating bolometers

    Science.gov (United States)

    Artusa, D. R.; Balzoni, A.; Beeman, J. W.; Bellini, F.; Biassoni, M.; Brofferio, C.; Camacho, A.; Capelli, S.; Cardani, L.; Carniti, P.; Casali, N.; Cassina, L.; Clemenza, M.; Cremonesi, O.; Cruciani, A.; D'Addabbo, A.; Dafinei, I.; Di Domizio, S.; di Vacri, M. L.; Ferroni, F.; Gironi, L.; Giuliani, A.; Gotti, C.; Keppel, G.; Maino, M.; Mancuso, M.; Martinez, M.; Morganti, S.; Nagorny, S. S.; Nastasi, M.; Nisi, S.; Nones, C.; Orlandi, D.; Pagnanini, L.; Pallavicini, M.; Palmieri, V.; Pattavina, L.; Pavan, M.; Pessina, G.; Pettinacci, V.; Pirro, S.; Pozzi, S.; Previtali, E.; Puiu, A.; Rusconi, C.; Schäffner, K.; Tomei, C.; Vignati, M.; Zolotarova, A.

    2017-09-01

    Future experiments on neutrinoless double beta-decay with the aim of exploring the inverted hierarchy region have to employ detectors with excellent energy resolution and zero background in the energy region of interest. Cryogenic scintillating bolometers turn out to be a suitable candidate since they offer particle discrimination: the dual channel detection of the heat and the scintillation light signal allows for particle identification. In particular such detectors permit for a suppression of α-induced backgrounds, a key-issue for next-generation tonne-scale bolometric experiments. We report on the progress and current status of the LUCIFER/CUPID-0 demonstrator, the first array of scintillating bolometers based on enriched Zn82Se crystals which is expected to start data taking in 2016 and the potential of this detection technique for a future tonne-scale bolometric experiment after CUORE.

  9. Design of a four-channel bolometer module for ASDEX upgrade and tore supra

    International Nuclear Information System (INIS)

    Mueller, E.R.; Weber, G.; Mast, F.; Schramm, G.; Buchelt, E.; Andelfinger, C.

    1985-10-01

    A new small-sized four-bolometer module for application in high-temperature plasma diagnostics has been designed. The four bolometers and the four reference bolometers shielded against radiation are placed side by side on one kapton foil, the entire arrangement occupying an area of 2.0x3.3 cm 2 . The central part of each bolometer consists of a 1.5x4 mm 2 large, 4 to 15 μm thick radiation absorber made of gold, a 7.5 μm thick kapton carrier foil, and a 0.05 μm thick meander-like gold resistor (conduction path width: 30 μm). It offers all the advantages already provided by the well-known ASDEX and JET bolometers, such as very high operating reliability and resistance to nuclear radiation damage. It is optional to enlarge the cooling time constant of the bolometer in a controlled way from a few milliseconds up to several hundreds, thus improving the sensitivity to very weak signals in the low-frequency (<=20 Hz) part of the radiation spectrum, by means of an additional (thin) gold layer that delays the heat losses from the bolometer foil to the cooling body. Since the bolometer is very suitable for AC-bridge electronics and all bridge resistors are arranged on a minimum area interference signals should be suppressed to extremely low levels. (orig.)

  10. All Metal Organic Deposited High-Tc Superconducting Transition Edge Bolometer on Yttria-Stabilized Zirconia Substrate

    DEFF Research Database (Denmark)

    Mohajeri, Roya; Opata, Yuri Aparecido; Wulff, Anders Christian

    2016-01-01

    of voltage amplitude and phase was analysed and measured through four-probe technique in a liquid nitrogen cooling system. An increase in voltage amplitude response was observed for the fabricated YBCO/CLO/YSZ bolometer compared to previously reported TEBs with similarly deposited YBCO thin film on a SrTiO3...

  11. Scintillating bolometers: A promising tool for rare decays search

    Energy Technology Data Exchange (ETDEWEB)

    Pattavina, L., E-mail: luca.pattavina@mib.infn.it

    2013-12-21

    The idea of using a scintillating bolometer was first suggested for solar neutrino experiments in 1989. After many years of developments, now we are able to exploit this experimental technique, based on the calorimetric approach with cryogenic particle detectors, to investigate rare events such as Neutrinoless Double Beta Decay and interaction of Dark Matter candidates. The possibility to have high resolution detectors in which a very large part of the natural background can be discriminated with respect to the weak expected signal is very appealing. The goal to distinguish the different types of interactions in the detector can be achieved by means of scintillating bolometer. The simultaneous read-out of the heat and scintillation signals made with two independent bolometers enable this precious feature leading to possible background free experiment. In the frame of the LUCIFER project we report on how exploiting this technique to investigate Double Beta Decay for different isotope candidates. Moreover we demonstrate how scintillating bolometers are suited for investigating other rare events such as α decays of long living isotopes of lead and bismuth.

  12. AC bias characterization of low noise bolometers for SAFARI using an open-loop frequency domain SQUID-based multiplexer operating between 1 and 5 MHz

    NARCIS (Netherlands)

    Gottardi, L.; Bruijn, M.; Gao, J.R.; Den Hartog, R.; Hijmering, R.; Hoevers, H.; Khosropanah, P.; De Korte, P.; Van der Kuur, J.; Lindeman, M.; Ridder, M.

    2012-01-01

    SRON is developing the Frequency Domain Multiplexing (FDM) read-out and the ultra low NEP TES bolometers array for the infra-red spectrometer SAFARI on board of the Japanese space mission SPICA. The FDM prototype of the instrument requires critical and complex optimizations. For single pixel

  13. A 16 channel frequency-domain-modulation readout system with custom superconducting LC filters for the SWIPE instrument of the balloon-borne LSPE experiment

    Energy Technology Data Exchange (ETDEWEB)

    Signorelli, G., E-mail: giovanni.signorelli@pi.infn.it [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Baldini, A.M. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Bemporad, C. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Università di Pisa, Dipartimento di Fisica, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Biasotti, M. [INFN Sezione di Genova and Università degli studi di Genova, Via Dodecaneso 33, 16146 Genova (Italy); Cei, F. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Università di Pisa, Dipartimento di Fisica, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Ceriale, V.; Corsini, D.; Fontanelli, F. [INFN Sezione di Genova and Università degli studi di Genova, Via Dodecaneso 33, 16146 Genova (Italy); Galli, L.; Gallucci, G. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Gatti, F. [INFN Sezione di Genova and Università degli studi di Genova, Via Dodecaneso 33, 16146 Genova (Italy); Incagli, M.; Grassi, M. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Nicolò, D. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Università di Pisa, Dipartimento di Fisica, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Spinella, F. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Vaccaro, D. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Università di Pisa, Dipartimento di Fisica, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Venturini, M. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa (Italy)

    2016-07-11

    We present the design, implementation and first tests of the superconducting LC filters for the frequency domain readout of spiderweb TES bolometers of the SWIPE experiment on the balloon-borne LSPE mission which aims at measuring the linear polarization of the Cosmic Microwave Background at large angular scales to find the imprint of inflation on the B-mode CMB polarization. LC filters are designed, produced and tested at the INFN sections of Pisa and Genoa where thin film deposition and cryogenic test facilities are present, and where also the TES spiderweb bolometers are being produced.

  14. An Ideal Integrating Bolometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a novel detector to enable a new class of far-IR spectroscopic surveys.  The detector, the Ideal Integrating Bolometer (IIB) is able to...

  15. Applications of superconducting bolometers in security imaging

    International Nuclear Information System (INIS)

    Luukanen, A; Leivo, M M; Rautiainen, A; Grönholm, M; Toivanen, H; Grönberg, L; Helistö, P; Mäyrä, A; Aikio, M; Luukanen, A; Grossman, E N

    2012-01-01

    Millimeter-wave (MMW) imaging systems are currently undergoing deployment World-wide for airport security screening applications. Security screening through MMW imaging is facilitated by the relatively good transmission of these wavelengths through common clothing materials. Given the long wavelength of operation (frequencies between 20 GHz to ∼ 100 GHz, corresponding to wavelengths between 1.5 cm and 3 mm), existing systems are suited for close-range imaging only due to substantial diffraction effects associated with practical aperture diameters. The present and arising security challenges call for systems that are capable of imaging concealed threat items at stand-off ranges beyond 5 meters at near video frame rates, requiring substantial increase in operating frequency in order to achieve useful spatial resolution. The construction of such imaging systems operating at several hundred GHz has been hindered by the lack of submm-wave low-noise amplifiers. In this paper we summarize our efforts in developing a submm-wave video camera which utilizes cryogenic antenna-coupled microbolometers as detectors. Whilst superconducting detectors impose the use of a cryogenic system, we argue that the resulting back-end complexity increase is a favorable trade-off compared to complex and expensive room temperature submm-wave LNAs both in performance and system cost.

  16. Controllable manipulation of superconductivity using magnetic vortices

    International Nuclear Information System (INIS)

    Villegas, J E; Schuller, Ivan K

    2011-01-01

    The magneto-transport of a superconducting/ferromagnetic hybrid structure, consisting of a superconducting thin film in contact with an array of magnetic nanodots in the so-called 'magnetic vortex state', exhibits interesting properties. For certain magnetic states, the stray magnetic field from the vortex array is intense enough to drive the superconducting film into the normal state. In this fashion, the normal-to-superconducting phase transition can be controlled by the magnetic history. The strong coupling between superconducting and magnetic subsystems allows characteristically ferromagnetic properties, such as hysteresis and remanence, to be dramatically transferred into the transport properties of the superconductor.

  17. The ITER bolometer diagnostic: Status and plans

    International Nuclear Information System (INIS)

    Meister, H.; Giannone, L.; Horton, L. D.; Raupp, G.; Zeidner, W.; Grunda, G.; Kalvin, S.; Fischer, U.; Serikov, A.; Stickel, S.; Reichle, R.

    2008-01-01

    A consortium consisting of four EURATOM Associations has been set up to develop the project plan for the full development of the ITER bolometer diagnostic and to continue urgent R and D activities. An overview of the current status is given, including detector development, line-of-sight optimization, performance analysis as well as the design of the diagnostic components and their integration in ITER. This is complemented by the presentation of plans for future activities required to successfully implement the bolometer diagnostic, ranging from the detector development over diagnostic design and prototype testing to RH tools for calibration.

  18. The ITER bolometer diagnostic: Status and plansa)

    Science.gov (United States)

    Meister, H.; Giannone, L.; Horton, L. D.; Raupp, G.; Zeidner, W.; Grunda, G.; Kalvin, S.; Fischer, U.; Serikov, A.; Stickel, S.; Reichle, R.

    2008-10-01

    A consortium consisting of four EURATOM Associations has been set up to develop the project plan for the full development of the ITER bolometer diagnostic and to continue urgent R&D activities. An overview of the current status is given, including detector development, line-of-sight optimization, performance analysis as well as the design of the diagnostic components and their integration in ITER. This is complemented by the presentation of plans for future activities required to successfully implement the bolometer diagnostic, ranging from the detector development over diagnostic design and prototype testing to RH tools for calibration.

  19. 1D goes 2D: A Berezinskii-Kosterlitz-Thouless transition in superconducting arrays of 4-Angstrom carbon nanotubes

    KAUST Repository

    Wang, Zhe

    2010-10-01

    We report superconducting resistive transition characteristics for array(s) of coupled 4-Angstrom single wall carbon nanotubes embedded in aluminophosphate-five zeolite. The transition was observed to initiate at 15 K with a slow resistance decrease switching to a sharp, order of magnitude drop between 7.5 and 6.0 K with strong (anisotropic) magnetic field dependence. Both the sharp resistance drop and its attendant nonlinear IV characteristics are consistent with the manifestations of a Berezinskii-Kosterlitz-Thouless transition that establishes quasi long range order in the plane transverse to the c-axis of the nanotubes, leading to an inhomogeneous system comprising 3D superconducting regions connected by weak links. Global coherence is established at below 5 K with the appearance of a well-defined supercurrent gap/low resistance region at 2 K. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Commercialization of Micro-fabrication of Antenna-Coupled Transition Edge Sensor Bolometer Detectors for Studies of the Cosmic Microwave Background

    Science.gov (United States)

    Suzuki, Aritoki; Bebek, Chris; Garcia-Sciveres, Maurice; Holland, Stephen; Kusaka, Akito; Lee, Adrian T.; Palaio, Nicholas; Roe, Natalie; Steinmetz, Leo

    2018-04-01

    We report on the development of commercially fabricated multichroic antenna-coupled transition edge sensor (TES) bolometer arrays for cosmic microwave background (CMB) polarimetry experiments. CMB polarimetry experiments have deployed instruments in stages. Stage II experiments deployed with O(1000) detectors and reported successful detection of B-mode (divergence-free) polarization pattern in the CMB. Stage III experiments have recently started observing with O(10,000) detectors with wider frequency coverage. A concept for a stage IV experiment, CMB-S4, is emerging to make a definitive measurement of CMB polarization from the ground with O(400,000) detectors. The orders of magnitude increase in detector count for CMB-S4 require a new approach in detector fabrication to increase fabrication throughput and reduce the cost. We report on collaborative efforts with two commercial micro-fabrication foundries to fabricate antenna-coupled TES bolometer detectors. The detector design is based on the sinuous antenna-coupled dichroic detector from the POLARBEAR-2 experiment. The TES bolometers showed the expected I-V response, and the RF performance agrees with the simulation. We will discuss the motivation, design consideration, fabrication processes, test results, and how industrial detector fabrication could be a path to fabricate hundreds of detector wafers for future CMB polarimetry experiments.

  1. TES arrays for the short wavelength band of the SAFARI instrument on SPICA

    Science.gov (United States)

    Khosropanah, P.; Hijmering, R.; Ridder, M.; Gao, J. R.; Morozov, D.; Mauskopf, P. D.; Trappe, N.; O'Sullivan, C.; Murphy, A.; Griffin, D.; Goldie, D.; Glowacka, D.; Withington, S.; Jackson, B. D.; Audley, M. D.; de Lange, G.

    2012-09-01

    SPICA is an infra-red (IR) telescope with a cryogenically cooled mirror (~5K) with three instruments on board, one of which is SAFARI that is an imaging Fourier Transform Spectrometer (FTS) with three bands covering the wavelength of 34-210 μm. We develop transition edge sensors (TES) array for short wavelength band (34-60 μm) of SAFARI. These are based on superconducting Ti/Au bilayer as TES bolometers with a Tc of about 105 mK and thin Ta film as IR absorbers on suspended silicon nitride (SiN) membranes. These membranes are supported by long and narrow SiN legs that act as weak thermal links between the TES and the bath. Previously an electrical noise equivalent power (NEP) of 4×10-19 W/√Hz was achieved for a single pixel of such detectors. As an intermediate step toward a full-size SAFARI array (43×43), we fabricated several 8×9 detector arrays. Here we describe the design and the outcome of the dark and optical tests of several of these devices. We achieved high yield (<93%) and high uniformity in terms of critical temperature (<5%) and normal resistance (7%) across the arrays. The measured dark NEPs are as low as 5×10-19 W/√Hz with a response time of about 1.4 ms at preferred operating bias point. The optical coupling is implemented using pyramidal horns array on the top and hemispherical cavity behind the chip that gives a measured total optical coupling efficiency of 30±7%.

  2. X-ray microcalorimeter arrays fabricated by surface micromachining

    International Nuclear Information System (INIS)

    Hilton, G.C.; Beall, J.A.; Deiker, S.; Vale, L.R.; Doriese, W.B.; Beyer, Joern; Ullom, J.N.; Reintsema, C.D.; Xu, Y.; Irwin, K.D.

    2004-01-01

    We are developing arrays of Mo/Cu transition edge sensor-based detectors for use as X-ray microcalorimeters and sub-millimeter bolometers. We have fabricated 8x8 pixel X-ray microcalorimeter arrays using surface micromachining. Surface-micromachining techniques hold the promise of scalability to much larger arrays and may allow for the integration of in-plane multiplexer elements. In this paper we describe the surface micromachining process and recent improvements in the device geometry that provide for increased mechanical strength. We also present X-ray and heat pulse spectra collected using these detectors

  3. LUCIFER: A Scintillating Bolometer Array for the Search of Neutrinoless Double Beta Decay

    International Nuclear Information System (INIS)

    Cardani, L

    2012-01-01

    One of the main limitations in the study of 0vDBD is the presence of a radioactive background in the energy region of interest. This limit can be overcome by the technological approach of the LUCIFER project, which is based the double read-out of the heat and scintillation light produced by ZnSe scintillating bolometers. This experiment aims at a background lower than 10 −3 counts/keV/kg/y in the energy region of the 0νDBD of 82 Se. Such a low background level will provide a sensitivity on the effective neutrino mass of the order of 100 meV. In the following, the results of the recent R and D activity are discussed, the single module for the LUCIFER detector is described, and the process for the production of 82 Se-enriched ZnSe crystals is presented.

  4. Comparison of Thermal Detector Arrays for Off-Axis THz Holography and Real-Time THz Imaging

    Directory of Open Access Journals (Sweden)

    Erwin Hack

    2016-02-01

    Full Text Available In terahertz (THz materials science, imaging by scanning prevails when low power THz sources are used. However, the application of array detectors operating with high power THz sources is increasingly reported. We compare the imaging properties of four different array detectors that are able to record THz radiation directly. Two micro-bolometer arrays are designed for infrared imaging in the 8–14 μm wavelength range, but are based on different absorber materials (i vanadium oxide; (ii amorphous silicon; (iii a micro-bolometer array optimized for recording THz radiation based on silicon nitride; and (iv a pyroelectric array detector for THz beam profile measurements. THz wavelengths of 96.5 μm, 118.8 μm, and 393.6 μm from a powerful far infrared laser were used to assess the technical performance in terms of signal to noise ratio, detector response and detectivity. The usefulness of the detectors for beam profiling and digital holography is assessed. Finally, the potential and limitation for real-time digital holography are discussed.

  5. Comparison of Thermal Detector Arrays for Off-Axis THz Holography and Real-Time THz Imaging.

    Science.gov (United States)

    Hack, Erwin; Valzania, Lorenzo; Gäumann, Gregory; Shalaby, Mostafa; Hauri, Christoph P; Zolliker, Peter

    2016-02-06

    In terahertz (THz) materials science, imaging by scanning prevails when low power THz sources are used. However, the application of array detectors operating with high power THz sources is increasingly reported. We compare the imaging properties of four different array detectors that are able to record THz radiation directly. Two micro-bolometer arrays are designed for infrared imaging in the 8-14 μm wavelength range, but are based on different absorber materials (i) vanadium oxide; (ii) amorphous silicon; (iii) a micro-bolometer array optimized for recording THz radiation based on silicon nitride; and (iv) a pyroelectric array detector for THz beam profile measurements. THz wavelengths of 96.5 μm, 118.8 μm, and 393.6 μm from a powerful far infrared laser were used to assess the technical performance in terms of signal to noise ratio, detector response and detectivity. The usefulness of the detectors for beam profiling and digital holography is assessed. Finally, the potential and limitation for real-time digital holography are discussed.

  6. Optical characterization of ultra-sensitive TES bolometers for SAFARI

    Science.gov (United States)

    Audley, Michael D.; de Lange, Gerhard; Gao, Jian-Rong; Khosropanah, Pourya; Mauskopf, Philip D.; Morozov, Dmitry; Trappe, Neil A.; Doherty, Stephen; Withington, Stafford

    2014-07-01

    We have characterized the optical response of prototype detectors for SAFARI, the far-infrared imaging spectrometer for the SPICA satellite. SAFARI's three bolometer arrays will image a 2'×2' field of view with spectral information over the wavelength range 34—210 μm. SAFARI requires extremely sensitive detectors (goal NEP ~ 0.2 aW/√Hz), with correspondingly low saturation powers (~5 fW), to take advantage of SPICA's cooled optics. We have constructed an ultra-low background optical test facility containing an internal cold black-body illuminator and have recently added an internal hot black-body source and a light-pipe for external illumination. We illustrate the performance of the test facility with results including spectral-response measurements. Based on an improved understanding of the optical throughput of the test facility we find an optical efficiency of 60% for prototype SAFARI detectors.

  7. Performance of resistive microcalorimeters and bolometers

    International Nuclear Information System (INIS)

    Galeazzi, M.

    2004-01-01

    Despite the impressive results achieved by microcalorimeters and bolometers, their performance is still significantly worse than that predicted by Mather's ideal model (Appl. Opt. 21 (1982) 1125). The difference is due both to non-ideal effects and to excess noise of unknown origin. The non-ideal effects have been recently quantified and include hot-electron effect, absorber decoupling, thermometer non-ohmic behavior, and all related extra noise sources. The excess noise affects primarily Transition Edge Sensors (TES) and is currently under experimental and theoretical investigation. This paper reviews the origin of non-ideal effects in microcalorimeters and bolometers and their effect on energy resolution and noise equivalent power. It also reviews the results on the characterization and suppression of the excess noise in TES, and the recent theoretical investigations to explain its origin in relation to fundamental physics in superconductors

  8. Operation of a tangential bolometer on the PBX tokamak

    International Nuclear Information System (INIS)

    Paul, S.F.; Fonck, R.J.; Schmidt, G.L.

    1987-04-01

    A compact 15-channel bolometer array that views plasma emission tangentially across the midplane has been installed on the PBX tokamak to supplement a 19-channel poloidal array which views the plasma perpendicular to the toroidal direction. By comparing measurements from these arrays, poloidal asymmetries in the emission profile can be assessed. The detector array consists of 15 discrete 2-mm x 2-mm Thinistors, a mixed semiconductor material whose temperature coefficient of resistance is relatively high. The accumulated heat incident on a detector gives rise to a change in the resistance in each active element. Operated in tandem with an identical blind detector, the resistance in each pair is compared in a Wheatstone bridge circuit. The variation in voltage resulting from the change in resistance is amplified, stored on a CAMAC transient recorder during the plasma discharge, and transferred to a VAX data acquisition computer. The instantaneous power is obtained by digitally smoothing and differentiating the signals in time, with suitable compensation for the cooling of the detector over the course of a plasma discharge. The detectors are ''free standing,'' i.e., they are supported only by their electrical leads. Having no substrate in contact with the detector reduces the response time and increases the time it takes for the detector to dissipate its accumulated heat, reducing the compensation for cooling required in the data analysis. The detectors were absolutely calibrated with a tungsten-halogen filament lamp and were found to vary by +-3%. The irradiance profiles are inverted to reveal the radially resolved emitted power density from the plasma, which is typically in the 0.1 to 0.5 W/cm 3 range

  9. High density processing electronics for superconducting tunnel junction x-ray detector arrays

    Energy Technology Data Exchange (ETDEWEB)

    Warburton, W.K., E-mail: bill@xia.com [XIA LLC, 31057 Genstar Road, Hayward, CA 94544 (United States); Harris, J.T. [XIA LLC, 31057 Genstar Road, Hayward, CA 94544 (United States); Friedrich, S. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)

    2015-06-01

    Superconducting tunnel junctions (STJs) are excellent soft x-ray (100–2000 eV) detectors, particularly for synchrotron applications, because of their ability to obtain energy resolutions below 10 eV at count rates approaching 10 kcps. In order to achieve useful solid detection angles with these very small detectors, they are typically deployed in large arrays – currently with 100+ elements, but with 1000 elements being contemplated. In this paper we review a 5-year effort to develop compact, computer controlled low-noise processing electronics for STJ detector arrays, focusing on the major issues encountered and our solutions to them. Of particular interest are our preamplifier design, which can set the STJ operating points under computer control and achieve 2.7 eV energy resolution; our low noise power supply, which produces only 2 nV/√Hz noise at the preamplifier's critical cascode node; our digital processing card that digitizes and digitally processes 32 channels; and an STJ I–V curve scanning algorithm that computes noise as a function of offset voltage, allowing an optimum operating point to be easily selected. With 32 preamplifiers laid out on a custom 3U EuroCard, and the 32 channel digital card in a 3U PXI card format, electronics for a 128 channel array occupy only two small chassis, each the size of a National Instruments 5-slot PXI crate, and allow full array control with simple extensions of existing beam line data collection packages.

  10. Anisotrophic currents and flux jumps in high-T-c superconducting films with self-organized arrays of planar defects

    DEFF Research Database (Denmark)

    Yurchenko, V.V.; Qviller, A.J.; Mozhaev, P.B.

    2010-01-01

    Regular arrays of planar defects with a period of a few nanometers can be introduced in superconducting YBa2Cu3O7-delta (YBCO) thin films by depositing them on vicinal (also called miscut or tilted) substrates. This results in the anisotropy of critical currents flowing in the plane of the film. ...

  11. High Temperature Superconductor Bolometers for Planetary Science

    Data.gov (United States)

    National Aeronautics and Space Administration — This work is a design study of an instrument optimized for JPL's novel high temperature superconductor bolometers. The work involves designing an imaging...

  12. Multichannel bolometer for radiation measurements on the TCA tokamak

    International Nuclear Information System (INIS)

    Joye, B.; Marmillod, P.; Nowak, S.

    1986-01-01

    A multichannel radiation bolometer has been developed for the Tokamak Chauffage Alfven (TCA) tokamak. It has 16 equally spaced chords that view the plasma through a narrow horizontal slit. Almost an entire vertical plasma cross section can be observed. The bolometer operates on the basis of a semiconducting element which serves as a temperature-dependent resistance. A new electronic circuit has been developed which takes advantage of the semiconductor characteristics of the detector by using feedback techniques. Measurements made with this instrument are discussed

  13. Status and Integrated Focal Plane Characterization of Simons Array - Cosmic Microwave Background Polarimetry Experiment

    Science.gov (United States)

    Roberts, Hayley; POLARBEAR

    2018-06-01

    Simons Array is a cosmic microwave background (CMB) polarization experiment located at 5,200 meter altitude site in the Atacama desert in Chile. The science goals of the Simons Array are to characterize the CMB B-mode signal from gravitational lensing, and search for B-mode polarization generated from inflationary gravitational waves.In 2012, POLARBEAR-1 (PB-1) began observations and the POLARBEAR team has published the first measurements of non-zero polarization B-mode polarization angular power spectrum where gravitational lensing of CMB is the dominant signal.POLARBEAR-2A (PB-2A), the first of three receivers of Simons Array, will have 7,588 polarization sensitive Transition Edge Sensor (TES) bolometers with frequencies 90 GHz and 150 GHz. This represents a factor of 6 increase in detector count compared to PB-1. Once Simons Array is fully deployed, the focal plane array will consist 22,764 TES bolometers across 90 GHz, 150 GHz, 220 GHz, and 270 GHz with a projected instantaneous sensitivity of 2.5 µK√s. Here we present the status of PB-2A and characterization of the integrated focal plane to be deployed summer of 2018.

  14. Design of a bolometer for total-energy measurement of the linear coherent light source pulsed X-ray laser

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, S. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore CA 94550 (United States)]. E-mail: Friedrich1@llnl.gov; Li, L. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore CA 94550 (United States); Ott, L.L. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore CA 94550 (United States); Kolgani, Rajeswari M. [Department of Physics, Geosciences and Astronomy, Towson University, 8000 York Avenue, Towson MD 21252 (United States); Yong, G.J. [Department of Physics, Geosciences and Astronomy, Towson University, 8000 York Avenue, Towson MD 21252 (United States); Ali, Z.A. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore CA 94550 (United States); Drury, O.B. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore CA 94550 (United States); Ables, E. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore CA 94550 (United States); Bionta, R.M. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore CA 94550 (United States)

    2006-04-15

    We are developing a cryogenic bolometer to measure the total energy of the linear coherent light source (LCLS) free electron X-ray laser to be built at the Stanford Linear Accelerator Center. The laser will produce ultrabright X-ray pulses in the energy range between 0.8 and 8 keV with {approx}10{sup 12} photons per {approx}200 fs pulse at a repeat interval of 8 ms, and will be accompanied by a halo of spontaneous undulator radiation. The bolometer is designed to determine the total energy of each laser pulse to within <0.1%, taking into account thermal and mechanical stress to prevent melting in the LCLS beam due to its high energy density. We propose to use a magnetoresistive Nd{sub (1-} {sub x} {sub )}Sr {sub x} MnO{sub 3} sensor array at the metal-insulator transition, where the composition x is adjusted to produce the desired transition temperature. We discuss design considerations and material choices, and present numerical simulations of the thermal response.

  15. Hot-electron bolometer terahertz mixers for the Herschel Space Observatory.

    Science.gov (United States)

    Cherednichenko, Sergey; Drakinskiy, Vladimir; Berg, Therese; Khosropanah, Pourya; Kollberg, Erik

    2008-03-01

    We report on low noise terahertz mixers (1.4-1.9 THz) 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 0.5 to 2.5 THz, with 30 GHz resolution) and also by measuring the mixer noise temperature at a limited number of discrete frequencies. The lowest mixer noise temperature recorded was 750 K [double sideband (DSB)] at 1.6 THz and 950 K DSB at 1.9 THz local oscillator (LO) frequencies. Averaged across the intermediate frequency band of 2.4-4.8 GHz, the mixer noise temperature was 1100 K DSB at 1.6 THz and 1450 K DSB at 1.9 THz 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 200-500 nW range.

  16. LUCIFER: a scintillating bolometer array for the search of neutrinoless double beta decay

    International Nuclear Information System (INIS)

    Cardani, Laura

    2011-01-01

    In spite of the high precision achieved in the field of neutrino oscillations, there are some fundamental questions that can not be addressed by a study of ths phenomenon. We do not know in fact the absolute mass of neutrino and weather it is a Dirac or a Majorana particle. The LUCIFER experiment, financed by the ERC-AdG, will play an important role in this field. This project aims to push beyond the actual technological limits the possibility of observation of the Neutrinoless Double Beta Decay (0νDBD). The detection of this extremely rare decay would indeed demonstrate that neutrino is a Majorana particle and, at the same time, would allow to set its absolute mass scale. LUCIFER will study the 0νDBD do 82 Se through ZnSe scintillating bolometers. Thanks to the simultaneous red-out of the heat and light produced by an interaction in the crystal, the background rate in the region of interest will be lower than 10 -3 counts/kg/keV/years. In the following, the expected performance of LUCIFER are discussed.

  17. Development of neutron-transmutation-doped germanium bolometer material

    International Nuclear Information System (INIS)

    Palaio, N.P.

    1983-08-01

    The behavior of lattice defects generated as a result of the neutron-transmutation-doping of germanium was studied as a function of annealing conditions using deep level transient spectroscopy (DLTS) and mobility measurements. DLTS and variable temperature Hall effect were also used to measure the activation of dopant impurities formed during the transmutation process. In additioon, a semi-automated method of attaching wires on to small chips of germanium ( 3 ) for the fabrication of infrared detecting bolometers was developed. Finally, several different types of junction field effect transistors were tested for noise at room and low temperature (approx. 80 K) in order to find the optimum device available for first stage electronics in the bolometer signal amplification circuit

  18. Optical performance of prototype horn-coupled TES bolometer arrays for SAFARI

    Science.gov (United States)

    Audley, Michael D.; de Lange, Gert; Gao, Jian-Rong; Khosropanah, Pourya; Hijmering, Richard; Ridder, Marcel L.

    2016-07-01

    The SAFARI Detector Test Facility is an ultra-low background optical testbed for characterizing ultra-sensitive prototype horn-coupled TES bolmeters for SAFARI, the grating spectrometer on board the proposed SPICA satellite. The testbed contains internal cold and hot black-body illuminators and a light-pipe for illumination with an external source. We have added reimaging optics to facilitate array optical measurements. The system is now being used for optical testing of prototype detector arrays read out with frequency-domain multiplexing. We present our latest optical measurements of prototype arrays and discuss these in terms of the instrument performance.

  19. Experimental study of a SINIS detector response time at 350 GHz signal frequency

    Science.gov (United States)

    Lemzyakov, S.; Tarasov, M.; Mahashabde, S.; Yusupov, R.; Kuzmin, L.; Edelman, V.

    2018-03-01

    Response time constant of a SINIS bolometer integrated in an annular ring antenna was measured at a bath temperature of 100 mK. Samples comprising superconducting aluminium electrodes and normal-metal Al/Fe strip connected to electrodes via tunnel junctions were fabricated on oxidized Si substrate using shadow evaporation. The bolometer was illuminated by a fast black-body radiation source through a band-pass filter centered at 350 GHz with a passband of 7 GHz. Radiation source is a thin NiCr film on sapphire substrate. For rectangular 10÷100 μs current pulse the radiation front edge was rather sharp due to low thermal capacitance of NiCr film and low thermal conductivity of substrate at temperatures in the range 1-4 K. The rise time of the response was ~1-10 μs. This time presumably is limited by technical reasons: high dynamic resistance of series array of bolometers and capacitance of a long twisted pair wiring from SINIS bolometer to a room-temperature amplifier.

  20. Upcoming planetary missions and the applicability of high-temperature-superconductor bolometers

    International Nuclear Information System (INIS)

    Brasunas, J.; Kunde, V.; Moseley, H.; Lakew, B.

    1991-01-01

    Planetary missions to Mars and beyond can last 11 years and longer, making impractical the use of stored cryogens. Passive radiative coolers and single-stage mechanical coolers remain possibilities. Cassini and Comet Rendezvous/Asteroid Fly-by (CRAF), both using the newly developed Mariner Mark 2 spacecraft, will be the next outer planet missions after Galileo; they are intended to provide information on the origin and evolution of the solar system. CRAF is slated for a 1994 launch. Cassini was chosen by ESA and will be launched by a Titan 4/Centaur in 1996. It will fly by Jupiter in 2000, inject an ESA-supplied probe into Titan in 2002, and take data in Saturn's orbit from 2002 to 2006. NASA/Goddard is currently developing a prototype Fourier transform spectrometer, the Composite Infrared Spectrometer (CIRS), for the Cassini mission. The baseline infrared detectors for CIRS are HgCdTe to 16 microns and Schwarz-type thermopiles from 16 to 1000 microns. The far infrared focal plane could be switched from thermopiles to high temperature superconductor (HTS) bolometers between now and 1996. An HTS bolometer could be built using the kinetic inductance effect, or the sharp resistance change at the transition. The transition-edge bolometer is more straightforward to implement, and initial efforts at NASA/Goddard are directed to that device. A working device was made and tested in early 1989. It also has somewhat elevated noise levels below 100 Hz. Upcoming efforts will center on reducing the time constant of the HTS bolometer by attempting to deposit an HTS film on a diamond substrate, and by thinning SrTiO3 substrates. Attempts will be made to improve the film quality to reduce the 1/4 noise level, and to improve the thermal isolation to increase the bolometer sensitivity

  1. Terahertz performance of quasioptical front-ends with a hotelectron bolometer

    International Nuclear Information System (INIS)

    Semenov, A; Richter, H; Guenther, B; Huebers, H-W; Karamarkovic, J

    2006-01-01

    We present terahertz performance of quasioptical front-ends consisting of a hotelectron bolometer imbedded in a planar feed antenna and integrated with an immersion lens. The impedance and radiation pattern of the log-spiral and double-slot planar feeds are evaluated using the method of moments; the collimating action of the lens is modelled using the physical optics. The total efficiency of the front-ends is computed taking into account frequency dependent impedance of the bolometer. Measured performance of the front-ends qualifies the simulation technique as a reliable tool for the design of terahertz receivers

  2. Composite vortex ordering in superconducting films with arrays of blind holes

    International Nuclear Information System (INIS)

    Berdiyorov, G R; Milosevic, M V; Peeters, F M

    2009-01-01

    The pinning properties of a superconducting thin film with a square array of blind holes are studied using the nonlinear Ginzburg-Landau theory. Although blind holes provide a weaker pinning potential than holes (also called antidots), several novel vortex structures are predicted for different size and thickness of the blind holes. Orientational dimer and trimer vortex states as well as concentric vortex shells can nucleate in the blind holes. In addition, we predict the stabilization of giant vortices that may be located both in the pinning centers and/or at the interstitial sites, as well as the combination of giant vortices with sets of individual vortices. For large blind holes, local vortex shell structures inside the blind holes may transfer their symmetry to interstitial vortices as well. The subtle interplay of shell formation and traditional Abrikosov vortex lattices inside the blind holes is also studied for different numbers of trapped vortices.

  3. Nonlinear vibration behaviors of high-Tc superconducting bulks in an applied permanent magnetic array field

    Science.gov (United States)

    Li, Jipeng; Li, Haitao; Zheng, Jun; Zheng, Botian; Huang, Huan; Deng, Zigang

    2017-06-01

    The nonlinear vibration of high temperature superconducting (HTS) bulks in an applied permanent magnetic array (Halbach array) field, as a precondition for commercial application to HTS maglev train and HTS bearing, is systematically investigated. This article reports the actual vibration rules of HTS bulks from three aspects. First, we propose a new numerical model to simplify the calculation of levitation force. This model could provide precise simulations, especially the estimation of eigenfrequency. Second, an approximate analytic solution of the vibration of the HTS bulks is obtained by using the method of harmonic balance. Finally, to verify the results mentioned above, we measure the vertical vibration acceleration signals of an HTS maglev model, consisting of eight YBaCuO bulks, oscillating freely above a Halbach array with large displacement excitation. Higher order harmonic components, which indicate the nonlinear vibration phenomenon, are detected in the responses. All the three results are compared and agreed well with each other. This study combines the experimental and theoretical analyses and provides a deep understanding of the physical phenomenon of the nonlinear vibration and is meaningful for the vibration control of the relevant applications.

  4. Infrared detection with high-[Tc] bolometers and response of Nb tunnel junctions to picosecond voltage pulses

    Energy Technology Data Exchange (ETDEWEB)

    Verghese, S.

    1993-05-01

    Oxide superconductors with high critical temperature [Tc] make sensitive thermometers for several types of infrared bolometers. The authors built composite bolometers with YBa[sub 2]Cu[sub 3]O[sub 7[minus][delta

  5. Towards local oscillators based on arrays of niobium Josephson junctions

    International Nuclear Information System (INIS)

    Galin, M A; Klushin, A M; Kurin, V V; Seliverstov, S V; Finkel, M I; Goltsman, G N; Müller, F; Scheller, T; Semenov, A D

    2015-01-01

    Various applications in the field of terahertz technology are in urgent need of compact, wide-tunable solid-state continuous wave radiation sources with a moderate power. However, satisfactory solutions for the THz frequency range are scarce yet. Here we report on coherent radiation from a large planar array of Josephson junctions (JJs) in the frequency range between 0.1 and 0.3 THz. The external resonator providing the synchronization of JJ array is identified as a straight fragment of a single-strip-line containing the junctions themselves. We demonstrate a prototype of the quasioptical heterodyne receiver with the JJ array as a local oscillator and a hot-electron bolometer mixer. (paper)

  6. Millimetre wave attenuation of prototype diagnostic components for the ITER bolometers

    Energy Technology Data Exchange (ETDEWEB)

    Meister, H., E-mail: meister@ipp.mpg.de [Max-Planck-Institut für Plasmaphysik, Garching (Germany); Kasparek, W. [Universität Stuttgart, Institut für Grenzflächenverfahrenstechnik & Plasmatechnologie, Stuttgart (Germany); Zhang, D.; Hirsch, M. [Max-Planck-Institut für Plasmaphysik, Teilinstitut Greifswald, Greifswald (Germany); Koll, J. [Max-Planck-Institut für Plasmaphysik, Garching (Germany); Zeitler, A. [Universität Stuttgart, Institut für Grenzflächenverfahrenstechnik & Plasmatechnologie, Stuttgart (Germany)

    2015-10-15

    Highlights: • Attenuation of ECRH stray radiation in ITER demonstrated for bolometer prototypes. • Collimator with microwave reflecting grid achieves >70 dB at 170 GHz (ITER frequency). • For frequencies >250 GHz (ECE radiation) ceramic coating showed 40 dB attenuation. • Good shielding at joints of components is prerequisite to prevent microwave leakage. • These methods prevent the impact of ECRH stray radiation on bolometer measurements. - Abstract: Bolometers in current and future fusion devices, in particular those in ITER, are vulnerable to stray radiation from electron cyclotron resonance heating (ECRH) which results in measurement errors for plasma radiation detection. To protect the detectors from this stray radiation in the millimetre wavelength range, dedicated diagnostic components have been designed and tested. One option is to place a top plate which contains a microwave-reflecting grid onto the collimators. Another option investigated is the coating of the collimator channels using a microwave absorbing ceramic. Measurements of the mm-wave attenuation of the collimator in front of the bolometer detectors with and without top plate or coated collimator channels have been performed in the frequency range of 125–420 GHz. The attenuation factor of the collimator channels at 170 GHz (the ECRH frequency for ITER) with neither microwave grid nor coating is typically 10 dB. The coating enhances this to 40 dB and including the microwave grid yields at least an attenuation factor of 70 dB, which is sufficient to reduce the residual ECRH induced signal significantly below the one due to plasma radiation. Placing a bolometer camera (collimator connected to detector housing) inside the isotropic microwave field of the test facility MISTRAL, the attenuation factor of the full diagnostic set-up using a top plate was determined to be in the order of 45 dB. This degraded attenuation implies that particular attention has to be paid to design and quality

  7. An alternative geometry for bolometer sensors for use at high operating temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Meister, H., E-mail: meister@ipp.mpg.de [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, D-85748 Garching b. München (Germany); Langer, H. [KRP-Mechatec Engineering GbR, Lichtenbergstr. 8, D-85748 Garching b. München (Germany); Schmitt, S. [Fraunhofer ICT-IMM, Carl-Zeiss-Str. 18-20, D-55129 Mainz (Germany)

    2016-11-15

    Highlights: • Alternative design for bolometer sensors based on flexure hinges is proposed. • FE analysis confirms mechanical stability at high temperatures. • First prototypes successfully pass thermal cycling tests. • Expected bolometer calibration constants are estimated. • Tests using fully functional prototypes have to confirm applicability of design. - Abstract: Bolometer sensors are a key component to determine the total radiation and the radiation profile in fusion devices. For future devices like ITER the need arose to develop new sensors in order to adapt to loads, in particular neutron irradiation and enhanced thermal loads. The method proposed here to deal effectively with the stresses in the absorber and its supporting membrane is to support the absorber by flexure hinges, thus allowing deformations in all dimensions and reducing stresses. First, a design for the flexure hinges is proposed. Then finite-element analyses (FEA) have been carried out to investigate expected deformations due to residual stresses from the manufacturing process as well as due to additional thermal loads at 450 °C. The results showed stress levels below the expected tensile strength of Si. In addition, calculations show that the proposed design is expected to provide acceptable cooling time constants. Thus, prototypes based on the proposed design have been manufactured. Measurements of their deformation at room temperature are in agreement with predictions from FEA. Also, all prototypes were successfully subjected to thermal cycling up to 450 °C without any failures, thus demonstrating a successful development. However, for future application as bolometer sensor, a change in calibration parameters is expected: a factor of five for the heat capacity and a factor of two for the cooling time constant. Further prototypes including meanders and electrical contacts need to be developed and tested to finally validate if flexure hinges are a viable means for bolometer

  8. Real-time imaging systems for superconducting nanowire single-photon detector arrays

    Energy Technology Data Exchange (ETDEWEB)

    Hofherr, Matthias

    2014-07-01

    Superconducting nanowire singe-photon detectors (SNSPD) are promising detectors in the field of applications, where single-photon resolution is required like in quantum optics, spectroscopy or astronomy. These cryogenic detectors gain from a broad spectrum in the optical and infrared range and deliver low dark counts and low jitter. This work provides a piece of deeper physical understanding of detector functionality in combination with highly engineered readout development. A detailed analysis focuses on the intrinsic detection mechanism of SNSPDs related to the detection in the infrared regime and the evolution of dark counts. With this fundamental knowledge, the next step is the development of a multi-pixel readout at cryogenic conditions. It is demonstrated, how two auspicious multi-pixel readout concepts can be realized, which enables statistical framing like in imaging applications using RSFQ electronics with fast framing rates and the readout of a detector array with continuous real-time single-photon resolution.

  9. Josephson junction arrays and superconducting wire networks

    International Nuclear Information System (INIS)

    Lobb, C.J.

    1992-01-01

    Techniques used to fabricate integrated circuits make it possible to construct superconducting networks containing as many as 10 6 wires or Josephson junctions. Such networks undergo phase transitions from resistive high-temperature states to ordered low-resistance low-temperature states. The nature of the phase transition depends strongly on controllable parameters such as the strength of the superconductivity in each wire or junction and the external magnetic field. This paper will review the physics of these phase transitions, starting with the simplest zero-magnetic field case. This leads to a Kosterlitz-Thouless transition when the junctions or wires are weak, and a simple mean-field fransition when the junctions or wires are strong. Rich behavior, resulting from frustration, occurs in the presence of a magnetic field. (orig.)

  10. Emergent Higgsless Superconductivity

    Directory of Open Access Journals (Sweden)

    Cristina Diamantini M.

    2017-01-01

    Full Text Available We present a new Higgsless model of superconductivity, inspired from anyon superconductivity but P- and T-invariant and generalizable to any dimension. While the original anyon superconductivity mechanism was based on incompressible quantum Hall fluids as average field states, our mechanism involves topological insulators as average field states. In D space dimensions it involves a (D-1-form fictitious pseudovector gauge field which originates from the condensation of topological defects in compact lowenergy effective BF theories. There is no massive Higgs scalar as there is no local order parameter. When electromagnetism is switched on, the photon acquires mass by the topological BF mechanism. Although the charge of the gapless mode (2 and the topological order (4 are the same as those of the standard Higgs model, the two models of superconductivity are clearly different since the origins of the gap, reflected in the high-energy sectors are totally different. In 2D thi! s type of superconductivity is explicitly realized as global superconductivity in Josephson junction arrays. In 3D this model predicts a possible phase transition from topological insulators to Higgsless superconductors.

  11. Radiation detection from phase-locked serial dc SQUID arrays

    DEFF Research Database (Denmark)

    Kaplunenko, V. K.; Mygind, Jesper; Pedersen, Niels Falsig

    1993-01-01

    We report on synchronous operation of series arrays of inductively coupled superconducting quantum interference devices (SQUIDs). Each array consisted of N=3 or 11 dc SQUIDs with common inductances providing a strong interaction between neighboring cells. Externally shunted (betac[approximately-e......We report on synchronous operation of series arrays of inductively coupled superconducting quantum interference devices (SQUIDs). Each array consisted of N=3 or 11 dc SQUIDs with common inductances providing a strong interaction between neighboring cells. Externally shunted (betac...

  12. Superconducting transition edge sensors and methods for design and manufacture thereof

    Science.gov (United States)

    Sadleir, John E. (Inventor)

    2013-01-01

    Methods for forming sensors using transition edge sensors (TES) and sensors therefrom are described. The method includes forming a plurality of sensor arrays includes at least one TES device. The TES device includes a TES device body, a first superconducting lead contacting a first portion of the TES device body, and a second superconducting lead contacting of a second portion of the TES device body, where the first and second superconducting leads separated on the TES device body by a lead spacing. The lead spacing can be selected to be different for at least two of the plurality of sensor arrays. The method also includes determining a transition temperature for each of the plurality of sensor arrays and generating a signal responsive to detecting a change in the electrical characteristics of one of the plurality of sensor arrays meeting a transition temperature criterion.

  13. Neutron-transmutation-doped germanium bolometers

    International Nuclear Information System (INIS)

    Palaio, N.P.; Rodder, M.; Haller, E.E.; Kreysa, E.

    1983-02-01

    Six slices of ultra-pure germanium were irradiated with thermal neutron fluences between 7.5 x 10 16 and 1.88 x 10 18 cm - 2 . After thermal annealing the resistivity was measured down to low temperatures ( 0 exp(δ/T) in the hopping conduction regime. Also, several junction FETs were tested for noise performance at room temperature and in an insulating housing in a 4.2K cryostat. These FETs will be used as first stage amplifiers for neutron-transmutation-doped germanium bolometers

  14. The I{sub c}(H)-T{sub c}(H) phase boundary of superconducting Nb thin films with periodic and quasiperiodic antidot arrays

    Energy Technology Data Exchange (ETDEWEB)

    Bothner, D.; Kemmler, M.; Cozma, R.; Kleiner, R.; Koelle, D. [Physikalisches Institut and Center for Collective Quantum Phenomena, Universitaet Tuebingen (Germany); Misko, V.; Peeters, F. [Departement Fysica, Universiteit Antwerpen (Belgium); Nori, F. [Advanced Science Institute, RIKEN (Japan)

    2011-07-01

    The magnetic field dependent critical current I{sub c}(H) of superconducting thin films with artificial defects strongly depends on the symmetry of the defect arrangement. Likewise the critical temperature T{sub c}(H) of superconducting wire networks is heavily influenced by the symmetry of the system. Here we present experimental data on the I{sub c}(H)-T{sub c}(H) phase boundary of Nb thin films with artificial defect lattices of different symmetries. For this purpose we fabricated 60 nm thick Nb films with antidots in periodic (triangular) and five different quasiperiodic arrangements. The parameters of the antidot arrays were varied to investigate the influence of antidot diameter and array density. Experiments were performed with high temperature stability ({delta}T<1 mK) at 0.5{<=}T/T{sub c}{<=}1. From the I-V-characteristics at variable H and T we extract I{sub c}(H) and T{sub c}(H) for different voltage and resistance criteria. The experimental data for the critical current density are compared with results from numerical molecular dynamics simulations.

  15. Magnetization Controlled Superconductivity in a Film with Magnetic Dots

    International Nuclear Information System (INIS)

    Lyuksyutov, I.F.; Pokrovsky, V.; Pokrovsky, V.

    1998-01-01

    We consider a superconducting film with a magnetic dots array (MDA) placed upon it. Magnetic moments of the dots are normal to the film and strong enough to create vortices in the superconducting film. Magnetic interaction between dots is negligible. Zero-field cooling leads to random magnetization of the MDA well above the superconducting temperature. With this cooling, the film is in a resistive state below the (expected) superconducting transition. Paradoxically, when field cooled, the film with MDA can be superconducting. copyright 1998 The American Physical Society

  16. An experimental study of antireflective coatings in Ge light detectors for scintillating bolometers

    Directory of Open Access Journals (Sweden)

    Mancuso M.

    2014-01-01

    Full Text Available Luminescent bolometers are double-readout devices able to measure simultaneously the phonon and the light yields after a particle interaction in the detector. This operation allows in some cases to tag the type of the interacting quantum, crucial issue for background control in rare event experiments such as the search for neutrinoless double beta decay and for interactions of particle dark matter candidates. The light detectors used in the LUCIFER and LUMINEU searches (projects aiming at the study of the double beta interesting candidates 82Se and 100Mo using ZnSe and ZnMoO4 scintillating bolometers consist of hyper-pure Ge thin slabs equipped with NTD thermistors. A substantial sensitivity improvement of the Ge light detectors can be obtained applying a proper anti-reflective coatings on the Ge side exposed to the luminescent bolometer. The present paper deals with the investigation of this aspect, proving and quantifying the positive effect of a SiO2 and a SiO coating and setting the experimental bases for future tests of other coating materials. The results confirm that an appropriate coating procedure helps in improving the sensitivity of bolometric light detectors by an important factor (in the range 20% – 35% and needs to be included in the recipe for the development of an optimized radio-pure scintillating bolometer.

  17. An experimental study of antireflective coatings in Ge light detectors for scintillating bolometers

    Science.gov (United States)

    Mancuso, M.; Beeman, J. W.; Giuliani, A.; Dumoulin, L.; Olivieri, E.; Pessina, G.; Plantevin, O.; Rusconi, C.; Tenconi, M.

    2014-01-01

    Luminescent bolometers are double-readout devices able to measure simultaneously the phonon and the light yields after a particle interaction in the detector. This operation allows in some cases to tag the type of the interacting quantum, crucial issue for background control in rare event experiments such as the search for neutrinoless double beta decay and for interactions of particle dark matter candidates. The light detectors used in the LUCIFER and LUMINEU searches (projects aiming at the study of the double beta interesting candidates 82Se and 100Mo using ZnSe and ZnMoO4 scintillating bolometers) consist of hyper-pure Ge thin slabs equipped with NTD thermistors. A substantial sensitivity improvement of the Ge light detectors can be obtained applying a proper anti-reflective coatings on the Ge side exposed to the luminescent bolometer. The present paper deals with the investigation of this aspect, proving and quantifying the positive effect of a SiO2 and a SiO coating and setting the experimental bases for future tests of other coating materials. The results confirm that an appropriate coating procedure helps in improving the sensitivity of bolometric light detectors by an important factor (in the range 20% - 35%) and needs to be included in the recipe for the development of an optimized radio-pure scintillating bolometer.

  18. Soldered Contact and Current Risetime Effects on Negative Polarity Wire Array Z-pinches

    International Nuclear Information System (INIS)

    Chalenski, D. A.; Kusse, B. R.; Greenly, J. B.; Blesener, I. C.; McBride, R. D.; Hammer, D. A.; Knapp, P. F.

    2009-01-01

    The Cornell University COBRA pulser is a nominal 1 MA machine, capable of driving up to 32 wire cylindrical Z-pinch arrays. COBRA can operate with variable current risetimes ranging from 100 ns to 200 ns (short and long pulse, respectively). Wires are typically strung with a ''press'' contact to the electrode hardware, where the wire is loosely pulled against the hardware and held there to establish electrical contact. The machine is normally negative, but a bolt-on convolute can be used to modify the current path and effectively produce positive polarity operation at the load.Previous research with single wires on a 1-5 kA pulser has shown that soldering the wire, thereby improving the wire/electrode contact, and operating in positive polarity can improve the energy deposition into the wire and enhance wire core expansion. Negative polarity showed no difference. Previous experiments on the negative polarity, 20 MA, 100 ns Z accelerator have shown that improving the contact improved the x-ray yield.Cornell data were collected on 16-wire Aluminum Z-pinch arrays in negative polarity. Experiments were conducted with both short and long current pulses with soldered and no-soldered wire/electrode contacts. The initiation, ablation, implosion and stagnation phases were compared for these four conditions. Time dependent x-ray signals were measured using diodes and diamond detectors. An inductive voltage monitor was used to infer minimum current radius achieved, as defined by a uniform shell of current moving radially inward, producing a time dependent inductance. Total energy data were collected with a metal-strip bolometer. Self-emission data were collected by an XUV 4-frame camera and an optical streak camera.In negative polarity and with short pulses, soldering appeared to produce a smaller radius pinch and decrease variations in the x-ray pulse shape. The bolometer, laser backlighter, 4-frame and streak cameras showed negligible differences in the initiation ablation

  19. SQIF Arrays as RF Sensors (Briefing Charts)

    National Research Council Canada - National Science Library

    Yukon, Stanford P

    2007-01-01

    ... (Superconducting Quantum Interference Filter) arrays may be employed as sensitive RF sensors. RF SQIF arrays fabricated with high Tc Josephson junctions can be cooled with small Sterling microcoolers...

  20. A front-end electronic system for large arrays of bolometers

    Science.gov (United States)

    Arnaboldi, C.; Carniti, P.; Cassina, L.; Gotti, C.; Liu, X.; Maino, M.; Pessina, G.; Rosenfeld, C.; Zhu, B. X.

    2018-02-01

    CUORE is an array of thermal calorimeters composed of 988 crystals held at about 10 mK, whose absorbed energy is read out with semiconductor thermistors. The composition of the crystal is TeO2, and the aim is the study of the double beta decay of 130Te on very long and stable runs. CUPID-0 is an array of 26 Zn82Se crystals with double thermistor readout to study the double beta decay of 82Se. In the present paper, we present an overview of the entire front-end electronic readout chain, from the preamplifier to the anti-aliasing filter. This overview includes motivations, design strategies, circuit implementation and performance results of the electronic system, including other auxiliary yet important elements like power supplies and the slow control communication system. The stringent requirements of stability on the very long experimental runs that are foreseen during CUORE and CUPID-0 operation, are achieved thanks to novel solutions of the front-end preamplifier and of the detector bias circuit setup.

  1. Magnetic and superconducting nanowires

    DEFF Research Database (Denmark)

    Piraux, L.; Encinas, A.; Vila, L.

    2005-01-01

    magnetic and superconducting nanowires. Using different approaches entailing measurements on both single wires and arrays, numerous interesting physical properties have been identified in relation to the nanoscopic dimensions of these materials. Finally, various novel applications of the nanowires are also...

  2. Josephson junction arrays

    International Nuclear Information System (INIS)

    Bindslev Hansen, J.; Lindelof, P.E.

    1985-01-01

    In this review we intend to cover recent work involving arrays of Josephson junctions. The work on such arrays falls naturally into three main areas of interest: 1. Technical applications of Josephson junction arrays for high-frequency devices. 2. Experimental studies of 2-D model systems (Kosterlitz-Thouless phase transition, commensurate-incommensurate transition in frustrated (flux) lattices). 3. Investigations of phenomena associated with non-equilibrium superconductivity in and around Josephson junctions (with high current density). (orig./BUD)

  3. 600 GHz resonant mode in a parallel array of Josephson tunnel junctions connected by superconducting microstrip lines

    DEFF Research Database (Denmark)

    Kaplunenko, V. K.; Larsen, Britt Hvolbæk; Mygind, Jesper

    1994-01-01

    on experimental and numerical investigations of a resonant step observed at a voltage corresponding to 600 GHz in the dc current-voltage characteristic of a parallel array of 20 identical small NbAl2O3Nb Josephson junctions interconnected by short sections of superconducting microstrip line. The junctions...... are mutually phase locked due to collective interaction with the line sections excited close to the half wavelength resonance. The phase locking range can be adjusted by means of an external dc magnetic field and the step size varies periodically with the magnetic field. The largest step corresponds...

  4. Vortex lattice in effective type-I superconducting films with periodic arrays of submicron holes

    International Nuclear Information System (INIS)

    Berdiyorov, G.R.; Milosevic, M.V.; Peeters, F.M.

    2006-01-01

    The vortex matter and related phenomena in superconducting films with periodic arrays of microholes (antidots) are studied within the nonlinear Ginzburg-Landau (GL) theory. By varying the GL parameter κ, the vortex-vortex interaction is fine tuned, from repulsive to attractive behavior. This interaction is of crucial importance for equilibrium vortex structures, the saturation number of the antidots, and the related quantities, such as critical current. Due to vortex attraction in effectively type-I samples, the giant-vortex state becomes energetically favorable (contrary to the type-II behavior). For the same reason, the number of vortices which can be captured by antidots, increases with decreasing κ. As a result, for given magnetic field, the critical current is larger for effectively type-I superconductors than in conventional type-II cases

  5. Simulation of magnetization and levitation properties of arrays of ring-shaped type-II superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jun, E-mail: linxj8686@163.com; Huang, Chenguang; Yong, Huadong; Zhou, Youhe, E-mail: zhouyh@lzu.edu.cn

    2017-03-15

    Highlights: • A strong magnetic coupling appears if the gap between the superconducting rings is small. • The saturation magnetization of superconducting rings is related to the radial gap but independent of the vertical gap. • The array of rings in a non-uniform field experiences a levitation force, which increases with increasing height or thickness of the rings. - Abstract: This paper presents an analysis of the magnetic and mechanical properties of arrays of superconducting rings arranged in axial, radial, and matrix configurations under different magnetic fields. In terms of the Bean's critical state model and the minimum magnetic energy method, the dependences of the magnetization and levitation behaviors on the geometry, number, and gap of the superconducting rings are obtained. The results show that when the applied field is spatially uniform, the magnetic property of the superconducting array is associated with the gaps between the rings. For the case of small gaps, the entire array becomes not easy to be fully penetrated by the induced currents, and the magnetic field profiles of which are almost the same as ones in a single large ring. If the superconducting array is fully penetrated, its saturation magnetization value is affected by the radial interval and, however, is almost independent of the vertical separation. When the applied field produced by a cylindrical permanent magnet is nonuniform, the superconducting array will be subjected to a levitation force. The levitation force increases monotonically and finally reaches a saturation value with increasing height or thickness of the rings, and such saturation value is closely related to the inner radius of the array.

  6. Symmetric dynamic behaviour of a superconducting proximity array with respect to field reversal

    International Nuclear Information System (INIS)

    Lankhorst, M; Poccia, N

    2017-01-01

    As the complexity of strongly correlated systems and high temperature superconductors increases, so does also the essential complexity of defects found in these materials and the complexity of the supercurrent pathways. It can be therefore convenient to realize a solid-state system with regular supercurrent pathways and without the disguising effects of disorder in order to capture the essential characteristics of a collective dynamics. Using a square array of superconducting islands placed on a normal metal, we observe a state in which magnetic field-induced vortices are frozen in the dimples of the egg crate potential by their strong repulsion interaction. In this system a dynamic vortex Mott insulator transition has been previously observed. In this work, we will show the symmetric dynamic behaviour with respect to field reversal and we will compare it with the asymmetric behaviour observed at the dynamic vortex Mott transition. (paper)

  7. Bolometer's development for the detection of dark matter; Instrumentation autour de bolometres pour la recherche de matiere sombre WIMPs

    Energy Technology Data Exchange (ETDEWEB)

    Yvon, D

    2000-06-01

    The author reviews his contributions to the use of bolometers (cryogenic detectors) for the detection of wimps (weakly interactive massive particles). Wimps are detected through their elastic scattering on the nuclei of the detector, a heat signal, luminescence or ionization can be simultaneously detected (at least 2 signals are necessary to discard photon interactions). Bolometers operate at low temperatures (< 50 mK) so they allow very low detection threshold and resolution (< keV) with a full energy conversion for recoiling nuclei. In Saclay the technology of bolometers based on simultaneous detection of heat and ionisation has been developed and improvements have been studied (NbSi thin films bolometers). The first results obtained in the framework of the Edelweiss collaboration are presented. Other developments based on infra-red bolometry (Planck surveyor and Archeops projects) are briefly described. In an appendix the operating principle of a bolometer is presented. (A.C.)

  8. Automated measurement of bolometer line of sight alignment and characteristics for application in ITER

    Energy Technology Data Exchange (ETDEWEB)

    Penzel, Florian Olivier

    2015-07-01

    The line of sight (LOS) alignment and characteristic of a bolometer camera used in a fusion experiment is a crucial parameter for the measurement accuracy of the diagnostic. A robot based LOS measurement device has been developed which allows the fully automatic measurement of the two dimensional transmission function of a bolometer camera. It has been used to optimize camera prototypes for ITER and has been successfully operated in the fusion experiment ASDEX Upgrade in order to measure the LOS alignment.

  9. Progress on Background-Limited Membrane-Isolated TES Bolometers for Far-IR/Submillimeter Spectroscopy

    Science.gov (United States)

    Kenyon, M.; Day, P. K.; Bradford, C. M.; Bock, J. J.; Leduc, H. G.

    2006-01-01

    To determine the lowest attainable phonon noise equivalent power (NEP) for membrane-isolation bolometers, we fabricated and measured the thermal conductance of suspended Si3N4 beams with different geometries via a noise thermometry technique. We measured beam cross-sectional areas ranging from 0.35 x 0.5 (micro)m(sup 2) to 135 x 1.0 (micro)m(sup 2) and beam lengths ranging from (micro)m to 8300 (micro)m. The measurements directly imply that membrane-isolation bolometers are capable of reaching a phonon noise equivalent power (NEP) of 4 x 10(sup -20)W/Hz(sup 1)/O . This NEP adequate for the Background-Limited Infrared-Submillimeter Spectrograph (BLISS) proposed for the Japanese SPICA observatory, and adequate for NASA's SAFIR observatory, a 10-meter, 4 K telescope to be deployed at L2. Further, we measured the heat capacity of a suspended Si3N4 membrane and show how this result implies that one can make membrane-isolation bolometers with a response time which is fast enough for BLISS.

  10. Flux penetration in a ferromagnetic/superconducting bilayer

    Energy Technology Data Exchange (ETDEWEB)

    Adamus, Z.; Cieplak, M.Z.; Abal' Oshev, A. [Polish Acad Sci, Inst Phys, PL-02668 Warsaw, (Poland); Konczykowski, M. [CEA/DSM/DRECAM, Laboratoire des Solides Irradies, F-91191 Gif Sur Yvette, (France); Konczykowski, M. [Ecole Polytech, CNRS - UMR 7642, F-91128 Palaiseau, (France); Cheng, X.M.; Zhu, L.Y.; Chien, C.L. [Johns Hopkins Univ, Dept Phys and Astron, Baltimore, MD 21218 (United States)

    2007-07-01

    An array of miniature Hall sensors is used to study the magnetic flux penetration in a ferromagnetic/superconducting bilayer consisting of Nb as a superconducting layer and Co/Pt multilayer with perpendicular magnetic anisotropy as a ferromagnetic layer, separated by an amorphous Si layer to avoid the proximity effect. It is found that the magnetic domains in the ferromagnetic layer create a large edge barrier in the superconducting layer which delays flux penetration. The smooth flux profiles observed in the absence of magnetic pinning change into terraced profiles in the presence of domains. (authors)

  11. Inductive fault current limiter based on multiple superconducting rings of small diameter

    International Nuclear Information System (INIS)

    Osorio, M R; Cabo, L; Veira, J A; Vidal, F

    2004-01-01

    We present a fault current limiter prototype based on the use of a secondary comprised of an array of magnetic cores of small sections, each one of them with several superconducting rings. The main advantage of this configuration is that it is easier to make small diameter superconducting rings which, in addition, are more homogeneous and allow better refrigeration. We then present detailed measurements that show that, in addition to these advantages, this prototype offers the same limitation performances than when using a unique core and a superconducting ring with an equivalent area as the array of small section cores

  12. Magnetic interaction between spatially extended superconducting tunnel junctions

    DEFF Research Database (Denmark)

    Grønbech-Jensen, Niels; Samuelsen, Mogens Rugholm

    2002-01-01

    A general description of magnetic interactions between superconducting tunnel junctions is given. The description covers a wide range of possible experimental systems, and we explicitly explore two experimentally relevant limits of coupled junctions. One is the limit of junctions with tunneling...... been considered through arrays of superconducting weak links based on semiconductor quantum wells with superconducting electrodes. We use the model to make direct interpretations of the published experiments and thereby propose that long-range magnetic interactions are responsible for the reported...

  13. Demonstration of a fully integrated superconducting receiver with a 2.7 THz quantum cascade laser.

    Science.gov (United States)

    Miao, Wei; Lou, Zheng; Xu, Gang-Yi; Hu, Jie; Li, Shao-Liang; Zhang, Wen; Zhou, Kang-Min; Yao, Qi-Jun; Zhang, Kun; Duan, Wen-Ying; Shi, Sheng-Cai; Colombelli, Raffaele; Beere, Harvey E; Ritchie, David A

    2015-02-23

    We demonstrate for the first time the integration of a superconducting hot electron bolometer (HEB) mixer and a quantum cascade laser (QCL) on the same 4-K stage of a single cryostat, which is of particular interest for terahertz (THz) HEB/QCL integrated heterodyne receivers for practical applications. Two key issues are addressed. Firstly, a low power consumption QCL is adopted for preventing its heat dissipation from destroying the HEB's superconductivity. Secondly, a simple spherical lens located on the same 4-K stage is introduced to optimize the coupling between the HEB and the QCL, which has relatively limited output power owing to low input direct current (DC) power. Note that simulation techniques are used to design the HEB/QCL integrated heterodyne receiver to avoid the need for mechanical tuning. The integrated HEB/QCL receiver shows an uncorrected noise temperature of 1500 K at 2.7 THz, which is better than the performance of the same receiver with all the components not integrated.

  14. Superconducting nanostructured materials

    International Nuclear Information System (INIS)

    Metlushko, V.

    1998-01-01

    Within the last year it has been realized that the remarkable properties of superconducting thin films containing a periodic array of defects (such as sub-micron sized holes) offer a new route for developing a novel superconducting materials based on precise control of microstructure by modern photolithography. A superconductor is a material which, when cooled below a certain temperature, loses all resistance to electricity. This means that superconducting materials can carry large electrical currents without any energy loss--but there are limits to how much current can flow before superconductivity is destroyed. The current at which superconductivity breaks down is called the critical current. The value of the critical current is determined by the balance of Lorentz forces and pinning forces acting on the flux lines in the superconductor. Lorentz forces proportional to the current flow tend to drive the flux lines into motion, which dissipates energy and destroys zero resistance. Pinning forces created by isolated defects in the microstructure oppose flux line motion and increase the critical current. Many kinds of artificial pinning centers have been proposed and developed to increase critical current performance, ranging from dispersal of small non-superconducting second phases to creation of defects by proton, neutron or heavy ion irradiation. In all of these methods, the pinning centers are randomly distributed over the superconducting material, causing them to operate well below their maximum efficiency. We are overcome this drawback by creating pinning centers in aperiodic lattice (see Fig 1) so that each pin site interacts strongly with only one or a few flux lines

  15. Neutron-transmutation-doped germanium bolometers

    Science.gov (United States)

    Palaio, N. P.; Rodder, M.; Haller, E. E.; Kreysa, E.

    1983-01-01

    Six slices of ultra-pure germanium were irradiated with thermal neutron fluences between 7.5 x 10 to the 16th and 1.88 x 10 to the 18th per sq cm. After thermal annealing the resistivity was measured down to low temperatures (less than 4.2 K) and found to follow the relationship rho = rho sub 0 exp(Delta/T) in the hopping conduction regime. Also, several junction FETs were tested for noise performance at room temperature and in an insulating housing in a 4.2 K cryostat. These FETs will be used as first stage amplifiers for neutron-transmutation-doped germanium bolometers.

  16. Uncooled infrared focal plane array imaging in China

    Science.gov (United States)

    Lei, Shuyu

    2015-06-01

    This article reviews the development of uncooled infrared focal plane array (UIFPA) imaging in China in the past decade. Sensors based on optical or electrical read-out mechanism were developed but the latter dominates the market. In resistive bolometers, VOx and amorphous silicon are still the two major thermal-sensing materials. The specifications of the IRFPA made by different manufactures were collected and compared. Currently more than five Chinese companies and institutions design and fabricate uncooled infrared focal plane array. Some devices have sensitivity as high as 30 mK; the largest array for commercial products is 640×512 and the smallest pixel size is 17 μm. Emphasis is given on the pixel MEMS design, ROIC design, fabrication, and packaging of the IRFPA manufactured by GWIC, especially on design for high sensitivities, low noise, better uniformity and linearity, better stabilization for whole working temperature range, full-digital design, etc.

  17. Depairing critical current achieved in superconducting thin films with through-thickness arrays of artificial pinning centers

    International Nuclear Information System (INIS)

    Dinner, Rafael B; Wimbush, Stuart C; MacManus-Driscoll, Judith L; Blamire, Mark G; Robinson, Adam P

    2011-01-01

    Large area arrays of through-thickness nanoscale pores have been milled into superconducting Nb thin films via a process utilizing anodized aluminum oxide thin film templates. These pores act as artificial flux pinning centers, increasing the superconducting critical current, J c , of the Nb films. By optimizing the process conditions including anodization time, pore size and milling time, J c values approaching and in some cases matching the Ginzburg-Landau depairing current of 30 MA cm -2 at 5 K have been achieved-a J c enhancement over as-deposited films of more than 50 times. In the field dependence of J c , a matching field corresponding to the areal pore density has also been clearly observed. The effect of backfilling the pores with magnetic material has then been investigated. While backfilling with Co has been successfully achieved, the effect of the magnetic material on J c has been found to be largely detrimental compared to voids, although a distinct influence of the magnetic material in producing a hysteretic J c versus applied field behavior has been observed. This behavior has been tested for compatibility with currently proposed models of magnetic pinning and found to be most closely explained by a model describing the magnetic attraction between the flux vortices and the magnetic inclusions.

  18. Ultra-low noise TES bolometer arrays for SAFARI instrument on SPICA

    Science.gov (United States)

    Khosropanah, P.; Suzuki, T.; Ridder, M. L.; Hijmering, R. A.; Akamatsu, H.; Gottardi, L.; van der Kuur, J.; Gao, J. R.; Jackson, B. D.

    2016-07-01

    SRON is developing ultra-low noise Transition Edge Sensors (TESs) based on a superconducting Ti/Au bilayer on a suspended SiN island with SiN legs for the SAFARI instrument aboard the SPICA mission. We successfully fabricated TESs with very narrow (0.5-0.7 μm) and thin (0.25 μm) SiN legs on different sizes of SiN islands using deep reactiveion etching process. The pixel size is 840x840 μm2 and there are variety of designs with and without optical absorbers. For TESs without absorbers, we measured electrical NEPs as low as <1x10-19 W/√Hz with response time of 0.3 ms and reached the phonon noise limit. Using TESs with absorbers, we quantified the darkness of our setup and confirmed a photon noise level of 2x10-19 W/√Hz.

  19. Hot-Electron Bolometer Mixers on Silicon-on-Insulator Substrates for Terahertz Frequencies

    Science.gov (United States)

    Skalare, Anders; Stern, Jeffrey; Bumble, Bruce; Maiwald, Frank

    2005-01-01

    A terahertz Hot-Electron Bolometer (HEB) mixer design using device substrates based on Silicon-On-Insulator (SOI) technology is described. This substrate technology allows very thin chips (6 pm) with almost arbitrary shape to be manufactured, so that they can be tightly fitted into a waveguide structure and operated at very high frequencies with only low risk for power leakages and resonance modes. The NbTiN-based bolometers are contacted by gold beam-leads, while other beamleads are used to hold the chip in place in the waveguide test fixture. The initial tests yielded an equivalent receiver noise temperature of 3460 K double-sideband at a local oscillator frequency of 1.462 THz and an intermediate frequency of 1.4 GHz.

  20. Data acquisition and real-time bolometer tomography using LabVIEW RT

    International Nuclear Information System (INIS)

    Giannone, L.; Eich, T.; Fuchs, J.C.; Ravindran, M.; Ruan, Q.; Wenzel, L.; Cerna, M.; Concezzi, S.

    2011-01-01

    The currently available multi-core PCI Express systems running LabVIEW RT (real-time), equipped with FPGA cards for data acquisition and real-time parallel signal processing, greatly shorten the design and implementation cycles of large-scale, real-time data acquisition and control systems. This paper details a data acquisition and real-time tomography system using LabVIEW RT for the bolometer diagnostic on the ASDEX Upgrade tokamak (Max Planck Institute for Plasma Physics, Garching, Germany). The transformation matrix for tomography is pre-computed based on the geometry of distributed radiation sources and sensors. A parallelized iterative algorithm is adapted to solve a constrained linear system for the reconstruction of the radiated power density. Real-time bolometer tomography is performed with LabVIEW RT. Using multi-core machines to execute the parallelized algorithm, a cycle time well below 1 ms is reached.

  1. Antenna-coupled TES bolometers for the SPIDER experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kuo, C.L. [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)]|[California Institute of Technology, 1200 E California Boulevard, Pasadena, CA 91125 (United States)]. E-mail: clkuo@astro.caltech.edu; Ade, P. [University of Wales, Cardiff, 5 The Parade, Cardiff, CF24 3YB, Wales (United Kingdom); Bock, J.J. [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)]|[California Institute of Technology, 1200 E California Boulevard, Pasadena, CA 91125 (United States); Day, P. [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)]|[California Institute of Technology, 1200 E California Boulevard, Pasadena, CA 91125 (United States); Goldin, A.; Golwala, S.; Hristov, V.; Jones, W.C.; Lange, A.E.; Rossinot, P.; Vayonakis, A.; Wang, G. [California Institute of Technology, 1200 E California Boulevard, Pasadena, CA 91125 (United States); Halpern, M. [University of British Columbia, 2329 West Mall, Vancouver, BC, V6T 1Z4 (Canada); Hilton, G.; Irwin, K. [National Institute of Standards and Technology, 325 Broadway, Boulder, CO (United States); Holmes, W.; Kenyon, M.; LeDuc, H.G. [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); MacTavish, C. [University of Toronto, 60 St. George Street, Toronto, ON, M5S 1A7 (Canada); Montroy, T.; Ruhl, J. [Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106 (United States); Netterfield, C.B. [University of Toronto, 60 St. George Street, Toronto, ON, M5S 1A7 (Canada); Yun, M. [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)]|[University of Pittsburgh, 348 Benedum Engineering Hall, Pittsburgh, PA 15261 (United States); Zmuidzinas, J. [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)]|[California Institute of Technology, 1200 E California Boulevard, Pasadena, CA 91125 (United States)

    2006-04-15

    SPIDER is a proposed balloon-borne experiment designed to search for the imprints of gravity waves on the polarization of the cosmic microwave background radiation. The required wide frequency coverage, large number of sensitive detectors, and the stringent power constraints on a balloon are made possible by antenna-coupled TES bolometers. Several prototype devices have been fabricated and optically characterized. Their spectral and angular responses agree well with the theoretical expectations.

  2. Status of NTD Ge bolometer material and devices

    International Nuclear Information System (INIS)

    Haller, E.E.; Haegel, N.M.; Park, I.S.

    1985-08-01

    This status report is a direct follow-up to the presentation given at the first IR Detector Technology Workshop which took place at NASA Ames Research Center on July 12 and 13, 1983. The conclusions which we presented at that meeting are still fully valid. In the meantime we have learned more about the physics of hopping conduction at very low temperatures which will be important for bolometer design and operation at ever decreasing temperatures. Resistivity measurements have been extended down to 50 mK. At such low temperatures, precise knowledge of the neutron capture cross sections sigma/sub n/ of the various Ge isotopes is critical if one is to make an accurate prediction of the dopant concentrations and compensation, and therefore resistivity, that will result from a given irradiation. We describe an empirical approach for obtaining the desired resistivity material and are in the process of conducting a set of experiments which will improve the knowledge of the effective sigma/sub n/ values for a given location in a particular reactor. A wider range of NTD Ge samples is now available. Noise measurements on bolometers with ion implanted contacts show that no 1/f noise component appears down to 1 Hz and probably lower. 4 refs., 5 figs

  3. Status of the Argonne superconducting-linac heavy-ion energy booster

    International Nuclear Information System (INIS)

    Aron, J.; Benaroya, R.; Bollinger, L.M.; Clifft, B.E.; Henning, W.; Johnson, K.W.; Nixon, J.M.; Markovich, P.; Shepard, K.W.

    1979-01-01

    A superconducting linac is being constructed to provide an energy booster for heavy ions from an FN tandem. By late 1980 the linac will consist of 24 independently-phased superconducting resonators, and will provide an effective accelerating potential of more than 25 MV. While the linac is under construction, completed sections are being used to provide useful beam for nuclear physics experiments. In the most recent run with beam (June 1979), an eight resonator array provided an effective accelerating potential of 9.3 MV. Operation of a 12 resonator array is scheduled to begin in October 1979

  4. Status of the Argonne superconducting-linac heavy-ion energy booster

    Energy Technology Data Exchange (ETDEWEB)

    Aron, J.; Benaroya, R.; Bollinger, L.M.; Clifft, B.E.; Henning, W.; Johnson, K.W.; Nixon, J.M.; Markovich, P.; Shepard, K.W.

    1979-01-01

    A superconducting linac is being constructed to provide an energy booster for heavy ions from an FN tandem. By late 1980 the linac will consist of 24 independently-phased superconducting resonators, and will provide an effective accelerating potential of more than 25 MV. While the linac is under construction, completed sections are being used to provide useful beam for nuclear physics experiments. In the most recent run with beam (June 1979), an eight resonator array provided an effective accelerating potential of 9.3 MV. Operation of a 12 resonator array is scheduled to begin in October 1979.

  5. Superconducting magnets for toroidal fusion reactors

    International Nuclear Information System (INIS)

    Haubenreich, P.N.

    1980-01-01

    Fusion reactors will soon be employing superconducting magnets to confine plasma in which deuterium and tritium (D-T) are fused to produce usable energy. At present there is one small confinement experiment with superconducting toroidal field (TF) coils: Tokamak 7 (T-7), in the USSR, which operates at 4 T. By 1983, six different 2.5 x 3.5-m D-shaped coils from six manufacturers in four countries will be assembled in a toroidal array in the Large Coil Test Facility (LCTF) at Oak Ridge National Laboratory (ORNL) for testing at fields up to 8 T. Soon afterwards ELMO Bumpy Torus (EBT-P) will begin operation at Oak Ridge with superconducting TF coils. At the same time there will be tokamaks with superconducting TF coils 2 to 3 m in diameter in the USSR and France. Toroidal field strength in these machines will range from 6 to 9 T. NbTi and Nb 3 Sn, bath cooling and forced flow, cryostable and metastable - various designs are being tried in this period when this new application of superconductivity is growing and maturing

  6. Terahertz imaging and spectroscopy based on hot electron bolometer (HEB) heterodyne detection

    Science.gov (United States)

    Gerecht, Eyal; You, Lixing

    2008-02-01

    Imaging and spectroscopy at terahertz frequencies have great potential for healthcare, plasma diagnostics, and homeland security applications. Terahertz frequencies correspond to energy level transitions of important molecules in biology and astrophysics. Terahertz radiation (T-rays) can penetrate clothing and, to some extent, can also penetrate biological materials. Because of their shorter wavelengths, they offer higher spatial resolution than do microwaves or millimeter waves. We are developing hot electron bolometer (HEB) mixer receivers for heterodyne detection at terahertz frequencies. HEB detectors provide unprecedented sensitivity and spectral resolution at terahertz frequencies. We describe the development of a two-pixel focal plane array (FPA) based on HEB technology. Furthermore, we have demonstrated a fully automated, two-dimensional scanning, passive imaging system based on our HEB technology operating at 0.85 THz. Our high spectral resolution terahertz imager has a total system noise equivalent temperature difference (NEΔT) value of better than 0.5 K and a spatial resolution of a few millimeters. HEB technology is becoming the basis for advanced terahertz imaging and spectroscopic technologies for the study of biological and chemical agents over the entire terahertz spectrum.

  7. Resistive transition of superconducting-wire networks. Influence of pinning and fluctuations

    International Nuclear Information System (INIS)

    Giroud, M.; Buisson, O.; Wang, Y.Y.; Pannetier, B.; Mailly, D.

    1992-01-01

    The authors studied the resistive transition of several 2-D superconducting-wire networks of various coupling strengths, which they characterize in terms of the Kosterlitz-Thouless transition temperature and the ratio ξ/a of the coherence length to the array period. In the extreme strong-coupling limit where the mesh size is of the order of the zero-temperature coherence length, the superconducting behavior is well described by the mean-field properties of the superconducting wave function. Extending to 2-D array, the 1-D phase-slippage model explains the dissipative regime observed above the Ginzburg-Landau depairing critical current. On the other hand, when the coupling is weak, phase fluctuations below the Ginzburg-Landau transition and vortex depinning dominate the resistive behavior. An activated dissipation is observed even below the depairing critical current. Results obtained in this regime for critical temperature, magnetoresistance, or critical current versus temperature, and magnetic field are shown; their periodic oscillations are discussed in terms of depinning of vortices on the array. A simple periodic pinning potential for a vortex in a wire network is calculated, and compared with the case of pinning in Josephson junction arrays. It is shown that this model explains qualitatively the experimental results observed for small ξ/a

  8. bicep2/KECK ARRAY. IV. OPTICAL CHARACTERIZATION AND PERFORMANCE OF THE bicep2 AND KECK ARRAY EXPERIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Ade, P. A. R. [School of Physics and Astronomy, Cardiff University, Cardiff, CF24 3AA (United Kingdom); Aikin, R. W.; Bock, J. J.; Brevik, J. A.; Filippini, J. P.; Golwala, S. R.; Hildebrandt, S. R.; Hui, H. [Department of Physics, California Institute of Technology, Pasadena, CA 91125 (United States); Barkats, D. [Joint ALMA Observatory, ESO, Santiago (Chile); Benton, S. J. [Department of Physics, University of Toronto, Toronto, ON (Canada); Bischoff, C. A.; Bradford, K. J.; Buder, I. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street MS 42, Cambridge, MA 02138 (United States); Bullock, E. [Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55455 (United States); Dowell, C. D. [Jet Propulsion Laboratory, Pasadena, CA 91109 (United States); Duband, L. [Université Grenoble Alpes, CEA INAC-SBT, F-38000 Grenoble (France); Fliescher, S. [Department of Physics, University of Minnesota, Minneapolis, MN 55455 (United States); Halpern, M.; Hasselfield, M. [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC (Canada); Hilton, G. C., E-mail: avieregg@kicp.uchicago.edu [National Institute of Standards and Technology, Boulder, CO 80305 (United States); Collaboration: bicep2 and Keck Array Collaborations; and others

    2015-06-20

    bicep2 and the Keck Array are polarization-sensitive microwave telescopes that observe the cosmic microwave background (CMB) from the South Pole at degree angular scales in search of a signature of inflation imprinted as B-mode polarization in the CMB. bicep2 was deployed in late 2009, observed for three years until the end of 2012 at 150 GHz with 512 antenna-coupled transition edge sensor bolometers, and has reported a detection of B-mode polarization on degree angular scales. The Keck Array was first deployed in late 2010 and will observe through 2016 with five receivers at several frequencies (95, 150, and 220 GHz). bicep2 and the Keck Array share a common optical design and employ the field-proven bicep1 strategy of using small-aperture, cold, on-axis refractive optics, providing excellent control of systematics while maintaining a large field of view. This design allows for full characterization of far-field optical performance using microwave sources on the ground. Here we describe the optical design of both instruments and report a full characterization of the optical performance and beams of bicep2 and the Keck Array at 150 GHz.

  9. Progress in the development of superconducting quadrupoles for heavy ion fusion

    International Nuclear Information System (INIS)

    Faltens, A.; Lietzke, A.; Sabbi, G.; Seidl, P.; Lund, S.; Manahan, B.; Martovetsky, N.; Gung, C.; Minervini, J.; Schultz, J.; Myatt, L.; Meinke, R.

    2002-01-01

    The Heavy Ion Fusion program is developing single aperture superconducting quadrupoles based on NbTi conductor, for use in the High Current Experiment at Lawrence Berkeley National Laboratory. Following the fabrication and testing of prototypes using two different approaches, a baseline design has been selected and further optimized. A prototype cryostat for a quadrupole doublet, with features to accommodate induction acceleration modules, is being fabricated. The single aperture magnet was derived from a conceptual design of a quadrupole array magnet for multi-beam transport. Progress on the development of superconducting quadrupole arrays for future experiments is also reported

  10. Progress in the development of superconducting quadrupoles for heavy ion fusion

    Energy Technology Data Exchange (ETDEWEB)

    Faltens, A.; Lietzke, A.; Sabbi, G.; Seidl, P.; Lund, S.; Manahan, B.; Martovetsky, N.; Gung, C.; Minervini, J.; Schultz, J.; Myatt, L.; Meinke, R.

    2002-05-24

    The Heavy Ion Fusion program is developing single aperture superconducting quadrupoles based on NbTi conductor, for use in the High Current Experiment at Lawrence Berkeley National Laboratory. Following the fabrication and testing of prototypes using two different approaches, a baseline design has been selected and further optimized. A prototype cryostat for a quadrupole doublet, with features to accommodate induction acceleration modules, is being fabricated. The single aperture magnet was derived from a conceptual design of a quadrupole array magnet for multi-beam transport. Progress on the development of superconducting quadrupole arrays for future experiments is also reported.

  11. Progress in the Development of Superconducting Quadrupoles forHeavy-ion Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Faltens, A.; Lietzke, A.; Sabbi, G.; Seidl, P.; Lund, S.; Manahan, R.; Martovetsky, N.; Gung, C.; Minervini, J.; Schultz, J.; Myatt, L.; Meinke, R.

    2002-08-19

    The Heavy Ion Fusion program is developing single aperture superconducting quadrupoles based on NbTi conductor, for use in the High Current Experiment at Lawrence Berkeley National Laboratory. Following the fabrication and testing of prototypes using two different approaches, a baseline design has been selected and further optimized. A prototype cryostat for a quadrupole doublet, with features to accommodate induction acceleration modules, is being fabricated. The single aperture magnet was derived from a conceptual design of a quadrupole array magnet for multi-beam transport. Progress on the development of superconducting quadrupole arrays for future experiments is also reported.

  12. Radiation detection at very low temperature. DRTBT 1999 - Balaruc-les-Bains - Course collection

    International Nuclear Information System (INIS)

    Chapellier, M.; Ravex, A.; Pari, P.; Bossy, J.; Garoche, P.; Perrin, Nicole; Loidl, M.; Den Hartog, Roland; Navick, Xavier-Francois; Mailly, Dominique; Chardin, Gabriel; Joyez, Philippe; Goyot, M.; Dumoulin, L.; Aprilli, M.; Torre, J.P.; Bouchez, J.; Benoit, Alain

    1992-01-01

    After four contributions (Introduction to cryogenics, Pulsed tube or recent developments in cryo-coolers, Dilution-based cooling, Adiabatic demagnetisation), the contributions addressed various themes: Low temperature physics (Specific and abnormal heats, Thermal conductivity, Anderson insulator, Superconductors); Physics within bolometers (basic principle of a bolometer, Energy conversion and ionisation, electron-phonon interaction, Edge sensor transition); Example of cryogenic sensors (Sub-millimetre / spider-web, Superconducting Tunnel Junction as photon detectors, ionization-heat massive bolometers); Signal processing (SQUID amplifiers, Elementary statistics, Signal processing and data analysis, Measurement electronics for bolometers, Single electron transistor, Preamplifiers)

  13. Assembly and Integration Process of the First High Density Detector Array for the Atacama Cosmology Telescope

    Science.gov (United States)

    Li, Yaqiong; Choi, Steve; Ho, Shuay-Pwu; Crowley, Kevin T.; Salatino, Maria; Simon, Sara M.; Staggs, Suzanne T.; Nati, Federico; Wollack, Edward J.

    2016-01-01

    The Advanced ACTPol (AdvACT) upgrade on the Atacama Cosmology Telescope (ACT) consists of multichroicTransition Edge Sensor (TES) detector arrays to measure the Cosmic Microwave Background (CMB) polarization anisotropies in multiple frequency bands. The first AdvACT detector array, sensitive to both 150 and 230 GHz, is fabricated on a 150 mm diameter wafer and read out with a completely different scheme compared to ACTPol. Approximately 2000 TES bolometers are packed into the wafer leading to both a much denser detector density and readout circuitry. The demonstration of the assembly and integration of the AdvACT arrays is important for the next generation CMB experiments, which will continue to increase the pixel number and density. We present the detailed assembly process of the first AdvACT detector array.

  14. Development of an automated method for in situ measurement of the geometrical properties of the ITER bolometer diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Meister, H., E-mail: meister@ipp.mpg.de; Penzel, F.; Giannone, L.; Kannamueller, M.; Kling, A.; Koll, J.; Trautmann, T.

    2011-10-15

    In order to derive the local emission profile of the plasma radiation in a fusion device using the line-integrated measurements of the bolometer diagnostic, tomographic reconstruction methods have to be applied to the measurements from many lines-of-sight. A successful reconstruction needs to take the finite sizes of detectors and apertures and the resulting non-ideal measurements into account. In ITER a method for in situ measurement of the geometrical properties of the various components of the bolometer diagnostic after installation is required as the viewing cones have to pass through narrow gaps between components. The method proposed to be used for ITER uses the beam of a laser with high intensity to illuminate the bolometer assembly from many different angles {xi} and {theta}. A light-weight robot from Kuka Robotics is used to efficiently position the laser on many points covering the complete viewing cone of each line-of-sight and to direct the beam precisely into the entrance aperture of the bolometer. Measuring the response of the bolometer allows for the calculation of the transmission function t({xi}, {theta}), the angular etendue and finally the geometric function in reconstruction space, which is required for the tomography algorithms. Measuring the transmission function for a laboratory assembly demonstrates the viability of the proposed method. Results for a collimator-type camera from a prototype envisaged for ITER are presented. The implemented procedure is discussed in detail, in particular with respect to the automatisation applied which takes the achievable positioning and alignment accuracies of the robot into account. This discussion is extended towards the definition of requirements for a remote-handling tool for ITER.

  15. High-Density Superconducting Cables for Advanced ACTPol

    Science.gov (United States)

    Pappas, C. G.; Austermann, J.; Beall, J. A.; Duff, S. M.; Gallardo, P. A.; Grace, E.; Henderson, S. W.; Ho, S. P.; Koopman, B. J.; Li, D.; McMahon, J.; Nati, F.; Niemack, M. D.; Niraula, P.; Salatino, M.; Schillaci, A.; Schmitt, B. L.; Simon, S. M.; Staggs, S. T.; Stevens, J. R.; Vavagiakis, E. M.; Ward, J. T.; Wollack, E. J.

    2016-07-01

    Advanced ACTPol (AdvACT) is an upcoming Atacama Cosmology Telescope (ACT) receiver upgrade, scheduled to deploy in 2016, that will allow measurement of the cosmic microwave background polarization and temperature to the highest precision yet with ACT. The AdvACT increase in sensitivity is partly provided by an increase in the number of transition-edge sensors (TESes) per array by up to a factor of two over the current ACTPol receiver detector arrays. The high-density AdvACT TES arrays require 70 \\upmu m pitch superconducting flexible cables (flex) to connect the detector wafer to the first-stage readout electronics. Here, we present the flex fabrication process and test results. For the flex wiring layer, we use a 400-nm-thick sputtered aluminum film. In the center of the cable, the wiring is supported by a polyimide substrate, which smoothly transitions to a bare (uncoated with polyimide) silicon substrate at the ends of the cable for a robust wedge wire-bonding interface. Tests on the first batch of flex made for the first AdvACT array show that the flex will meet the requirements for AdvACT, with a superconducting critical current above 1 mA at 500 mK, resilience to mechanical and cryogenic stress, and a room temperature yield of 97 %.

  16. High-Tc Superconducting Bolometer Noise Measurement Using Low Noise Transformers - Theory and Optimization

    Science.gov (United States)

    Aslam, Shahid; Jones, Hollis H.

    2011-01-01

    Care must always be taken when performing noise measurements on high-Tc superconducting materials to ensure that the results are not from the measurement system itself. One situation likely to occur is with low noise transformers. One of the least understood devices, it provides voltage gain for low impedance inputs (< 100 ), e.g., YBaCuO and GdBaCuO thin films, with comparatively lower noise levels than other devices for instance field effect and bipolar junction transistors. An essential point made in this paper is that because of the complex relationships between the transformer ports, input impedance variance alters the transformer s transfer function in particular, the low frequency cutoff shift. The transfer of external and intrinsic transformer noise to the output along with optimization and precautions are treated; all the while, we will cohesively connect the transfer function shift, the load impedance, and the actual noise at the transformer output.

  17. Diamagnetism in quasicrystalline superconducting networks

    International Nuclear Information System (INIS)

    Qian Niu; Nori, F.

    1990-01-01

    In this paper, we review recent results on superconducting structures with quasicrystalline geometry. Specifically, we consider the superconducting-normal phase boundaries of a variety of wire networks and Josephson junction arrays. We have computed the mean field phase diagrams for a number of geometries and compared them to the corresponding experimental data. We have introduced an analytical approach to the analysis of the structures present in the phase boundaries. Furthermore, we have shown in great detail how the gross structure is determined by the statistical distributions of the cell areas, and how the fine structures are determined by correlations among neighboring cells in the lattices. (author). 12 refs, 2 figs

  18. Transmission Level High Temperature Superconducting Fault Current Limiter

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, Gary [SuperPower, Inc., Schenectady, NY (United States)

    2016-10-05

    The primary objective of this project was to demonstrate the feasibility and reliability of utilizing high-temperature superconducting (HTS) materials in a Transmission Level Superconducting Fault Current Limiter (SFCL) application. During the project, the type of high-temperature superconducting material used evolved from 1st generation (1G) BSCCO-2212 melt cast bulk high-temperature superconductors to 2nd generation (2G) YBCO-based high-temperature superconducting tape. The SFCL employed SuperPower's “Matrix” technology, that offers modular features to enable scale up to transmission voltage levels. The SFCL consists of individual modules that contain elements and parallel inductors that assist in carrying the current during the fault. A number of these modules are arranged in an m x n array to form the current-limiting matrix.

  19. Studies of the Superconducting Transition in the Mo/Au-Bilayer Thin Films

    Science.gov (United States)

    Sadleir, John; Smith, Stephen; Iyomoto, naoko; Bandler, Simon; Chervenak, Jay; Brown, Ari; Brekowsky, Regis; Kilbourne, Caroline; Robinson, Ian

    2007-01-01

    At NASA Goddard, microcalorimeter arrays using superconducting transition edge sensor thermometers (TESs) are under development for high energy resolution X-ray astrophysics applications. We report on our studies of the superconducting transition in our Mo/Au-bilayer TES films including: low current measurements of the superconducting bilayer's resistance transition versus temperature on pixels with different normal metal absorber attachment designs and measured temperature scaling of the critical current and critical magnetic field.

  20. Development of transition edge superconducting bolometers for the SAFARI Far-Infrared spectrometer on the SPICA space-borne telescope

    NARCIS (Netherlands)

    Mauskopf, P.; Morozov, D.; Glowacka, D.; Goldie, D.; Withington, S.; Bruijn, M.; De Korte, P.; Hoevers, H.; Ridder, M.; Van der Kuur, J.; Gao, J.R.

    2008-01-01

    We describe the optimization of transition edge superconducting (TES) detectors for use in a far-infrared (FIR) Fourier transform spectrometer (FTS) mounted on a cryogenically cooled space-borne telescope (e.g. SPICA). The required noise equivalent power (NEP) of the detectors is approximately 10?19

  1. Characterization of a ZnSe scintillating bolometer prototype for neutrinoless double beta decay search

    Directory of Open Access Journals (Sweden)

    Tenconi M.

    2014-01-01

    Full Text Available As proposed in the LUCIFER project, ZnSe crystals are attractive materials to realize scintillating bolometers aiming at the search for neutrinoless double beta decay of the promising isotope 82Se. However, the optimization of the ZnSe-based detectors is rather complex and requires a wide-range investigation of the crystal features: optical properties, crystalline quality, scintillation yields and bolometric behaviour. Samples tested up to now show problems in the reproducibility of crucial aspects of the detector performance. In this work, we present the results obtained with a scintillating bolometer operated aboveground at about 25 mK. The detector energy absorber was a single 1 cm3 ZnSe crystal. The good energy resolution of the heat channel (about 14 keV at 1460 keV and the excellent alpha/beta discrimination capability are very encouraging for a successful realization of the LUCIFER program. The bolometric measurements were completed by optical tests on the crystal (optical transmission and luminescence measurements down to 10 K and investigation of the crystalline structure. The work here described provides a set of parameters and procedures useful for a complete pre-characterization of ZnSe crystals in view of the realization of highly performing scintillating bolometers.

  2. Superconducting nanowire networks formed on nanoporous membrane substrates

    Science.gov (United States)

    Luo, Qiong

    Introducing a regular array of holes into superconducting thin films has been actively pursued to stabilize and pin the vortex lattice against external driving forces, enabling higher current capabilities. If the width of the sections between neighboring holes is comparable to the superconducting coherence length, the circulation of the Cooper pairs in around the holes in the presence of a magnetic field can also produce the Little-Parks effect, i.e. periodic oscillation of the critical temperature. These two mechanisms, commensurate vortex pinning enhancement by the hole-array and the critical temperature oscillations of a wire network due to Little-Parks effect can induce similar experimental observations such as magnetoresistance oscillation and enhancement of the critical current at specific magnetic fields. This dissertation work investigates the effect of a hole-array on the properties of superconducting films deposited onto nanoporous substrates. Experiments on anisotropies of the critical temperature for niobium films on anodic aluminum oxide membrane substrates containing a regular hole-array reveal that the critical temperature exhibits two strong anisotropic effects: Little-Parks oscillations whose period varies with field direction superimposed on a smooth background arising from one dimensional confinement by the finite lateral space between neighboring holes. The two components of the anisotropy are intrinsically linked and appear in concert. That is, the hole-array changes the dimensionality of a two-dimensional (2D) film to a network of 1D nanowire network. Network of superconducting nanowires with transverse dimensions as small as few nanometers were achieved by coating molybdenum germanium (MoGe) layer onto commercially available filtration membranes which have extremely dense nanopores. The magnetoresistance, magnetic field dependence of the critical temperature and the anisotropies of the synthesized MoGe nanowire networks can be consistently

  3. Analysis of light propagation in quasiregular and hybrid Rudin-Shapiro one-dimensional photonic crystals with superconducting layers

    Science.gov (United States)

    Gómez-Urrea, H. A.; Escorcia-García, J.; Duque, C. A.; Mora-Ramos, M. E.

    2017-11-01

    The transmittance spectrum of a one-dimensional hybrid photonic crystal built from the suitable arrangement of periodic and quasiregular Rudin-Shapiro heterolayers that include superconducting slabs is investigated. The four-layer Rudin-Shapiro structure is designed with three lossless dielectric layers and a low-temperature superconductor one. The dielectric function of the superconducting layer is modeled by the two-fluid Gorter-Casimir theory, and the transmittance is calculated with the use of the transfer matrix method. The obtained results reveal the presence of a cut-off frequency fc - a forbidden frequency band for propagation - that can be manipulated by changing the width of the superconducting layer, the temperature and the order of the Rudin-Shapiro sequence. In addition, the spatial distribution of the electric field amplitude for the propagating TM modes is also discussed. It is found that the maximum of localized electric field relative intensity - which reaches a value of several tens - corresponds to the frequency values above to the cut-off frequency, at which, the effective dielectric function of the hybrid unit cell becomes zero. The proposed structure could be another possible system for optical device design for temperature-dependent optical devices such as stop-band filters, or as bolometers.

  4. Liquid helium-cooled MOSFET preamplifier for use with astronomical bolometer

    Science.gov (United States)

    Goebel, J. H.

    1977-01-01

    A liquid helium-cooled p-channel enhancement mode MOSFET, the 3N167, is found to have sufficiently low noise for use as a preamplifier with helium-cooled bolometers that are used in infrared astronomy. Its characteristics at 300, 77, and 4.2 K are presented. It is also shown to have useful application with certain photoconductive and photovoltaic infrared detectors.

  5. Surface Sensitive Bolometer for the CUORE background reduction

    International Nuclear Information System (INIS)

    Pedretti, M.; Foggetta, L.; Giuliani, A.; Nones, C.; Sangiorgio, S.

    2005-01-01

    The most critical point of the CUORE Project [CUORE Proposal, see the web page: http://crio.mib.infn.it/wig] is the background level (BKGL) in the neutrinoless double beta decay (0νββ) region that is dominated by degraded particles coming from materials that face the detectors. Surface Sensitive Bolometers (SSBs) have been developed in order to reduce the BKGL by means of an active background discrimination. The principle of this technique and the first results obtained are briefly described in the following paper

  6. Development of superconducting tunnel junction arrays for astronomical observations

    NARCIS (Netherlands)

    Martin, D.

    2007-01-01

    The original S-CAM1 and 2 systems were a first successful demonstration of a camera for optical astronomy based on superconducting sensors. However, a number of shortcomings were identified during the observing campaigns at the William Herschel Telescope at La Palma that triggered this work. As the

  7. The Quantum Socket: Wiring for Superconducting Qubits - Part 2

    Science.gov (United States)

    Bejanin, J. H.; McConkey, T. G.; Rinehart, J. R.; Bateman, J. D.; Earnest, C. T.; McRae, C. H.; Rohanizadegan, Y.; Shiri, D.; Mariantoni, M.; Penava, B.; Breul, P.; Royak, S.; Zapatka, M.; Fowler, A. G.

    Quantum computing research has reached a level of maturity where quantum error correction (QEC) codes can be executed on linear arrays of superconducting quantum bits (qubits). A truly scalable quantum computing architecture, however, based on practical QEC algorithms, requires nearest neighbor interaction between qubits on a two-dimensional array. Such an arrangement is not possible with techniques that rely on wire bonding. To address this issue, we have developed the quantum socket, a device based on three-dimensional wires that enables the control of superconducting qubits on a two-dimensional grid. In this talk, we present experimental results characterizing this type of wiring. We will show that the quantum socket performs exceptionally well for the transmission and reflection of microwave signals up to 10 GHz, while minimizing crosstalk between adjacent wires. Under realistic conditions, we measured an S21 of -5 dB at 6 GHz and an average crosstalk of -60 dB. We also describe time domain reflectometry results and arbitrary pulse transmission tests, showing that the quantum socket can be used to control superconducting qubits.

  8. Hafnium Films and Magnetic Shielding for TIME, A mm-Wavelength Spectrometer Array

    Science.gov (United States)

    Hunacek, J.; Bock, J.; Bradford, C. M.; Butler, V.; Chang, T.-C.; Cheng, Y.-T.; Cooray, A.; Crites, A.; Frez, C.; Hailey-Dunsheath, S.; Hoscheit, B.; Kim, D. W.; Li, C.-T.; Marrone, D.; Moncelsi, L.; Shirokoff, E.; Steinbach, B.; Sun, G.; Trumper, I.; Turner, A.; Uzgil, B.; Weber, A.; Zemcov, M.

    2018-04-01

    TIME is a mm-wavelength grating spectrometer array that will map fluctuations of the 157.7-μm emission line of singly ionized carbon ([CII]) during the epoch of reionization (redshift z ˜ 5-9). Sixty transition-edge sensor (TES) bolometers populate the output arc of each of the 32 spectrometers, for a total of 1920 detectors. Each bolometer consists of gold absorber on a ˜ 3 × 3 mm silicon nitride micro-mesh suspended near the corners by 1 × 1 × 500 μm silicon nitride legs targeting a photon-noise-dominated NEP ˜ 1 × 10^{-17} W/√{Hz} . Hafnium films are explored as a lower-T_c alternative to Ti (500 mK) for TIME TESs, allowing thicker support legs for improved yield. Hf T_c is shown to vary between 250 and 450 mK when varying the resident Ar pressure during deposition. Magnetic shielding designs and simulations are presented for the TIME first-stage SQUIDs. Total axial field suppression is predicted to be 5 × 10^7.

  9. Preliminary results of the US pool-boiling coils from the IFSMTF full-array tests

    International Nuclear Information System (INIS)

    Lue, J.W.; Dresner, L.; Lubell, M.S.; Luton, J.N.; McManamy, T.J.; Shen, S.S.

    1986-01-01

    The Large Coil Task to develop superconducting magnets for fusion reactors, is now in the midst of full-array tests in the International Fusion Superconducting Magnet Test Facility at Oak Ridge National Laboratory. Included in the test array are two pool-boiling coils designed and fabricated by US manufacturers, General Dynamics/Convair Division and General Electric/Union Carbide Corporation. So far, both coils have been energized to full design currents in the single-coil tests, and the General Dynamics coil has reached the design point in the first Standard-I full-array test. Both coils performed well in the charging experiments. Extensive heating tests and the heavy instrumentation of these coils have, however, revealed some generic limitations of large pool-boiling superconducting coils. Details of these results and their analyses are reported

  10. High-Density Superconducting Cables for Advanced ACTPol

    Science.gov (United States)

    Pappas, C. G.; Austermann, J.; Beall, J. A.; Duff, S. M.; Gallardo, P. A.; Grace, E.; Henderson, S. W.; Ho, S. P.; Koopman, B. J.; Li, D.; hide

    2016-01-01

    Advanced ACTPol (AdvACT) is an upcoming Atacama Cosmology Telescope (ACT) receiver upgrade, scheduled to deploy in 2016, that will allow measure- ment of the cosmic microwave background polarization and temperature to the highest precision yet with ACT. The AdvACT increase in sensitivity is partly provided by an increase in the number of transition-edge sensors (TESes) per array by up to a factor of two over the current ACTPol receiver detector arrays. The high-density AdvACT TES arrays require 70 µ m pitch superconducting flexible cables (flex) to connect the detec- tor wafer to the first-stage readout electronics. Here, we present the flex fabrication process and test results. For the flex wiring layer, we use a 400-nm-thick sputtered alu- minum film. In the center of the cable, the wiring is supported by a polyimide substrate, which smoothly transitions to a bare (uncoated with polyimide) silicon substrate at the ends of the cable for a robust wedge wire-bonding interface. Tests on the first batch of flex made for the first AdvACT array show that the flex will meet the requirements for AdvACT, with a superconducting critical current above 1 mA at 500 mK, resilience to mechanical and cryogenic stress, and a room temperature yield of 97%.

  11. Fraunhofer regime of operation for superconducting quantum interference filters

    DEFF Research Database (Denmark)

    Shadrin, A.V.; Constantinian, K.Y.; Ovsyannikov, G.A.

    2008-01-01

    Series arrays of superconducting quantum interference devices (SQUIDs) with incommensurate loop areas, so-called superconducting quantum interference filters (SQIFs), are investigated in the kilohertz and the gigahertz frequency range. In SQIFs made of high-T-c bicrystal junctions the flux...... range of more than 60 dB in the kilohertz range. In the 1-2 GHz range the estimated power gain is 20 dB and the magnetic flux noise level is as low as 10(-4)Phi(0)....

  12. Uncooled Terahertz real-time imaging 2D arrays developed at LETI: present status and perspectives

    Science.gov (United States)

    Simoens, François; Meilhan, Jérôme; Dussopt, Laurent; Nicolas, Jean-Alain; Monnier, Nicolas; Sicard, Gilles; Siligaris, Alexandre; Hiberty, Bruno

    2017-05-01

    As for other imaging sensor markets, whatever is the technology, the commercial spread of terahertz (THz) cameras has to fulfil simultaneously the criteria of high sensitivity and low cost and SWAP (size, weight and power). Monolithic silicon-based 2D sensors integrated in uncooled THz real-time cameras are good candidates to meet these requirements. Over the past decade, LETI has been studying and developing such arrays with two complimentary technological approaches, i.e. antenna-coupled silicon bolometers and CMOS Field Effect Transistors (FET), both being compatible to standard silicon microelectronics processes. LETI has leveraged its know-how in thermal infrared bolometer sensors in developing a proprietary architecture for THz sensing. High technological maturity has been achieved as illustrated by the demonstration of fast scanning of large field of view and the recent birth of a commercial camera. In the FET-based THz field, recent works have been focused on innovative CMOS read-out-integrated circuit designs. The studied architectures take advantage of the large pixel pitch to enhance the flexibility and the sensitivity: an embedded in-pixel configurable signal processing chain dramatically reduces the noise. Video sequences at 100 frames per second using our 31x31 pixels 2D Focal Plane Arrays (FPA) have been achieved. The authors describe the present status of these developments and perspectives of performance evolutions are discussed. Several experimental imaging tests are also presented in order to illustrate the capabilities of these arrays to address industrial applications such as non-destructive testing (NDT), security or quality control of food.

  13. Bosonic Confinement and Coherence in Disordered Nanodiamond Arrays.

    Science.gov (United States)

    Zhang, Gufei; Samuely, Tomas; Du, Hongchu; Xu, Zheng; Liu, Liwang; Onufriienko, Oleksandr; May, Paul W; Vanacken, Johan; Szabó, Pavol; Kačmarčík, Jozef; Yuan, Haifeng; Samuely, Peter; Dunin-Borkowski, Rafal E; Hofkens, Johan; Moshchalkov, Victor V

    2017-11-28

    In the presence of disorder, superconductivity exhibits short-range characteristics linked to localized Cooper pairs which are responsible for anomalous phase transitions and the emergence of quantum states such as the bosonic insulating state. Complementary to well-studied homogeneously disordered superconductors, superconductor-normal hybrid arrays provide tunable realizations of the degree of granular disorder for studying anomalous quantum phase transitions. Here, we investigate the superconductor-bosonic dirty metal transition in disordered nanodiamond arrays as a function of the dispersion of intergrain spacing, which ranges from angstroms to micrometers. By monitoring the evolved superconducting gaps and diminished coherence peaks in the single-quasiparticle density of states, we link the destruction of the superconducting state and the emergence of bosonic dirty metallic state to breaking of the global phase coherence and persistence of the localized Cooper pairs. The observed resistive bosonic phase transitions are well modeled using a series-parallel circuit in the framework of bosonic confinement and coherence.

  14. Superconducting frustration bit

    International Nuclear Information System (INIS)

    Tanaka, Y.

    2014-01-01

    Highlights: • A frustration bit element is proposed for a conventional superconducting circuit. • It is composed of π-junctions. • It mimics the multiband superconductor. - Abstract: A basic design is proposed for a classical bit element of a superconducting circuit that mimics a frustrated multiband superconductor and is composed of an array of π-Josephson junctions (π-junction). The phase shift of π provides the lowest energy for one π-junction, but neither a π nor a zero phase shift gives the lowest energy for an assembly of π-junctions. There are two chiral states that can be used to store one bit information. The energy scale for reading and writing to memory is of the same order as the junction energy, and is thus in the same order of the driving energy of the circuit. In addition, random access is also possible

  15. Superconducting low-velocity linac for the Argonne positive-ion injector

    International Nuclear Information System (INIS)

    Shepard, K.W.; Markovich, P.K.; Zinkann, G.P.; Clifft, B.; Benaroya, R.

    1989-01-01

    A low-velocity superconducting linac has been developed as part of a positive-ion injector system, which is replacing a 9 MV tandem as the injector for the ATLAS accelerator. The linac consists of an independently phased array of resonators, and is designed to accelerate various ions over a velocity range .008 < v/c < .06. The resonator array is formed of four different types of superconducting interdigital structures. The linac is being constructed in three phases, each of which will cover the full velocity range. Successive phases will increase the total accelerating potential and permit heavier ions to be accelerated. Assembly of the first phase was completed in early 1989. In initial tests with beam, a five-resonator array provided approximately 3.5 MV of accelerating potential and operated without difficulty for several hundred hours. The second phase is scheduled for completion in late 1989, and will increase the accelerating potential to more than 8 MV. 5 refs., 2 figs., 1 tab

  16. Superconducting low-velocity linac for the Argonne positive-ion injector

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K.W.; Markovich, P.K.; Zinkann, G.P.; Clifft, B.; Benaroya, R.

    1989-01-01

    A low-velocity superconducting linac has been developed as part of a positive-ion injector system, which is replacing a 9 MV tandem as the injector for the ATLAS accelerator. The linac consists of an independently phased array of resonators, and is designed to accelerate various ions over a velocity range .008 < v/c < .06. The resonator array is formed of four different types of superconducting interdigital structures. The linac is being constructed in three phases, each of which will cover the full velocity range. Successive phases will increase the total accelerating potential and permit heavier ions to be accelerated. Assembly of the first phase was completed in early 1989. In initial tests with beam, a five-resonator array provided approximately 3.5 MV of accelerating potential and operated without difficulty for several hundred hours. The second phase is scheduled for completion in late 1989, and will increase the accelerating potential to more than 8 MV. 5 refs., 2 figs., 1 tab.

  17. Quantum Devices Bonded Beneath a Superconducting Shield: Part 2

    Science.gov (United States)

    McRae, Corey Rae; Abdallah, Adel; Bejanin, Jeremy; Earnest, Carolyn; McConkey, Thomas; Pagel, Zachary; Mariantoni, Matteo

    The next-generation quantum computer will rely on physical quantum bits (qubits) organized into arrays to form error-robust logical qubits. In the superconducting quantum circuit implementation, this architecture will require the use of larger and larger chip sizes. In order for on-chip superconducting quantum computers to be scalable, various issues found in large chips must be addressed, including the suppression of box modes (due to the sample holder) and the suppression of slot modes (due to fractured ground planes). By bonding a metallized shield layer over a superconducting circuit using thin-film indium as a bonding agent, we have demonstrated proof of concept of an extensible circuit architecture that holds the key to the suppression of spurious modes. Microwave characterization of shielded transmission lines and measurement of superconducting resonators were compared to identical unshielded devices. The elimination of box modes was investigated, as well as bond characteristics including bond homogeneity and the presence of a superconducting connection.

  18. Transition-Edge Hot-Electron Microbolometers for Millimeter and Submillimeter Astrophysics

    Science.gov (United States)

    Hsieh, Wen-Ting; Stevenson, Thomas; U-yen, Kongpop; Wollack, Edward; Barrentine, Emily

    2014-01-01

    The millimeter and the submillimeter wavelengths of the electromagnetic spectrum hold a wealth of information about the evolution of the universe. In particular, cosmic microwave background (CMB) radiation and its polarization carry the oldest information in the universe, and provide the best test of the inflationary paradigm available to astronomy today. Detecting gravity waves through their imprint on the CMB polarization would have extraordinary repercussions for cosmology and physics. A transition-edge hot-electron micro - bolometer (THM) consists of a superconducting bilayer transition-edge sensor (TES) with a thin-film absorber. Unlike traditional monolithic bolometers that make use of micromachined structures, the THM em ploys the decoupling between electrons and phonons at millikelvin temperatures to provide thermal isolation. The devices are fabricated photolithographically and are easily integrated with antennas via microstrip transmission lines, and with SQUID (superconducting quantum interference device) readouts. The small volume of the absorber and TES produces a short thermal time constant that facilitates rapid sky scanning. The THM consists of a thin-film metal absorber overlapping a superconducting TES. The absorber forms the termination of a superconducting microstripline that carries RF power from an antenna. The purpose of forming a separate absorber and TES is to allow flexibility in the optimization of the two components. In particular, the absorbing film's impedance can be chosen to match the antenna, while the TES impedance can be chosen to match to the readout SQUID amplifier. This scheme combines the advantages of the TES with the advantages of planar millimeter-wave transmission line circuits. Antenna-coupling to the detectors via planar transmission lines allows the detector dimensions to be much smaller than a wavelength, so the technique can be extended across the entire microwave, millimeter, and submillimeter wavelength ranges. The

  19. Measurements of the optical performance of bolometers for SPICA/SAFARI

    Science.gov (United States)

    Audley, Michael D.; de Lange, Gert; Gao, Jian-Rong; Khosropanah, Pourya; Ridder, Marcel; Ferrari, Lorenza; Laauwen, Wouter M.; Ranjan, Manisha; Mauskopf, Philip D.; Morozov, Dmitry; Trappe, Neil A.

    2012-09-01

    We have measured the optical response of detectors designed for SAFARI, the far-infrared imaging spectrometer for the SPICA satellite. To take advantage of SPICA's cooled optics, SAFARI’s three bolometer arrays are populated with extremely sensitive (NEP~2×10-19 W/√Hz) transition edge sensors with a transition temperature close to 100 mK. The extreme sensitivity and low saturation power (~4 fW) of SAFARI’s detectors present challenges to characterizing them. We have therefore built up an ultra-low background test facility with a cryogen-free high-capacity dilution refrigerator, paying careful attention to stray-light exclusion. Our use of a pulse-tube cooler to pre-cool the dilution refrigerator required that the SAFARI Detector System Test Facility provide a high degree electrical, magnetic, and mechanical isolation for the detectors. We have carefully characterized the performance of the test facility in terms of background power loading. The test facility has been designed to be flexible and easily reconfigurable with internal illuminators that allow us to characterize the optical response of the detectors. We describe the test facility and some of the steps we took to create an ultra-low background test environment. We have measured the optical response of two detectors designed for SAFARI’s short-wave wavelength band in combination with a spherical backshort and conical feedhorn. We find an overall optical efficiency of 40% for both, compared with an ideal-case predicted optical efficiency of 66%.

  20. Status of rf superconductivity at Argonne National Laboratory

    International Nuclear Information System (INIS)

    Markovich, P.M.; Shepard, K.W.; Zinkann, G.P.

    1987-01-01

    This paper reports the status of hardware development for the linac portion of the Argonne tandem-linac accelerator system (ATLAS). The ATLAS superconducting linac consists of an independent-phased array of 45 superconducting niobium resonators of the split-ring type. The linac has been operating in its present form since 1985, on a 24-hours per day, 5 days per week schedule. An upgrade of the ATLAS system is currently under construction the positive-ion injector (PII). The PII system will consist of an ECR positive-ion source mounted on a high-voltage platform injecting a very-low-velocity superconducting linac. The completed system will provide for the acceleration of beams of mass up to uranium, and will replace the tandem electrostatic accelerator as the injector for ATLAS. The status of resonator development for the superconducting linac is reported in this paper. Accelerating gradients in the existing ATLAS linac are currently limited by excessive heating and rf loss in the fast-tuning system associated with each superconducting resonator. Development of an upgraded fast-tuning system is also reported here. 7 refs., 5 figs

  1. European roadmap on superconductive electronics - status and perspectives

    International Nuclear Information System (INIS)

    Anders, S.; Blamire, M.G.; Buchholz, F.-Im.; Crete, D.-G.; Cristiano, R.; Febvre, P.; Fritzsch, L.; Herr, A.; Il'ichev, E.; Kohlmann, J.; Kunert, J.; Meyer, H.-G.; Niemeyer, J.; Ortlepp, T.; Rogalla, H.; Schurig, T.

    2010-01-01

    other applications SQUIDs are used as sensors for magnetic heart and brain signals in medical applications, as sensor for geological surveying and food-processing and for non-destructive testing. As amplifiers of electrical signals, SQUIDs can nearly reach the theoretical limit given by Quantum Mechanics. A further important field of application is the detection of very weak signals by 'transition-edge' bolometers, superconducting nanowire single-photon detectors, and superconductive tunnel junctions. Their application as radiation detectors in a wide frequency range, from microwaves to X-rays is now standard. The very low losses of superconductors have led to commercial microwave filter designs that are now widely used in the USA in base stations for cellular phones and in military communication applications. The number of demonstrated applications is continuously increasing and there is no area in professional electronics, in which superconductive electronics cannot be applied and surpasses the performance of classical devices. Superconductive electronics has to be cooled to very low temperatures. Whereas this was a bottleneck in the past, cooling techniques have made a huge step forward in recent years: very compact systems with high reliability and a wide range of cooling power are available commercially, from microcoolers of match-box size with milli-Watt cooling power to high-reliability coolers of many Watts of cooling power for satellite applications. Superconductive electronics will not replace semiconductor electronics and similar room-temperature techniques in standard applications, but for those applications which require very high speed, low-power consumption, extreme sensitivity or extremely high precision, superconductive electronics is superior to all other available techniques. To strengthen the European competitiveness in superconductor electronics research projects have to be set-up in the following field: - Ultra-sensitive sensing and imaging

  2. Cryogen-free cryostat for large-scale arrays of superconducting tunnel junction ion detectors in time-of-flight mass spectrometry

    Science.gov (United States)

    Kushino, A.; Ohkubo, M.; Chen, Y. E.; Ukibe, M.; Kasai, S.; Fujioka, K.

    2006-04-01

    Nb-based superconducting tunnel junction (STJ) detectors have a fast time resolution of a few 100 ns and high operating temperature of 0.3 K. These advantages expand their applicable fields to time-of-flight mass spectrometry (TOF-MS). In order to enlarge effective detection area, we have built arrays based on hundreds of large STJ elements. To realize the fast readout and no-cross talk, coaxial cables made of low-thermal conductivity materials were investigated. From results of thermal conduction measurements, we chose thin coaxial cables with a diameter of 0.33 mm, consisting of CuNi center/outer conductors and Teflon insulator for the wiring between 0.3 K- 3He pot of the sorption pump and 3 K-2nd stage of GM cooler. Even after the installation of coaxial cables and a cold snout to the cryogen-free cryostat, we could keep arrays at 0.3 K for about a week, and reduction of the holding time at 0.3 K and temperature rise at 3He pot due to the installation were small, ˜0.5 day and 10 mK, respectively.

  3. The First Multichroic Polarimeter Array on the Atacama Cosmology Telescope: Characterization and Performance

    Science.gov (United States)

    Ho, S. P.; Pappas, C. G.; Austermann, J.; Beall, J. A.; Becker, D.; Choi, S. K.; Datta, R.; Duff, S. M.; Gallardo, P. A.; Grace, E.; hide

    2016-01-01

    The Atacama Cosmology Telescope Polarimeter (ACTPol) is a polarization sensitive receiver for the 6-meter Atacama Cosmology Telescope (ACT) and measures the small angular scale polarization anisotropies in the cosmic microwave background (CMB). The full focal plane is composed of three detector arrays, containing over 3000 transition edge sensors (TES detectors) in total. The first two detector arrays, observing at 146 gigahertz, were deployed in 2013 and 2014, respectively. The third and final array is composed of multichroic pixels sensitive to both 90 and 146 gigahertz and saw first light in February 2015. Fabricated at NIST, this dichroic array consists of 255 pixels, with a total of 1020 polarization sensitive bolometers and is coupled to the telescope with a monolithic array of broad-band silicon feedhorns. The detectors are read out using time-division SQUID multiplexing and cooled by a dilution refrigerator at 110 meter Kelvins. We present an overview of the assembly and characterization of this multichroic array in the lab, and the initial detector performance in Chile. The detector array has a TES detector electrical yield of 85 percent, a total array sensitivity of less than 10 microns Kelvin root mean square speed, and detector time constants and saturation powers suitable for ACT CMB observations.

  4. The First Multichroic Polarimeter Array on the Atacama Cosmology Telescope: Characterization and Performance

    Science.gov (United States)

    Ho, S. P.; Pappas, C. G.; Austermann, J.; Beall, J. A.; Becker, D.; Choi, S. K.; Datta, R.; Duff, S. M.; Gallardo, P. A.; Grace, E.; Hasselfield, M.; Henderson, S. W.; Hilton, G. C.; Hubmayr, J.; Koopman, B. J.; Lanen, J. V.; Li, D.; McMahon, J.; Nati, F.; Niemack, M. D.; Niraula, P.; Salatino, M.; Schillaci, A.; Schmitt, B. L.; Simon, S. M.; Staggs, S. T.; Stevens, J. R.; Ward, J. T.; Wollack, E. J.; Vavagiakis, E. M.

    2016-08-01

    The Atacama Cosmology Telescope Polarimeter (ACTPol) is a polarization sensitive receiver for the 6-m Atacama Cosmology Telescope (ACT) and measures the small angular scale polarization anisotropies in the cosmic microwave background (CMB). The full focal plane is composed of three detector arrays, containing over 3000 transition edge sensors (TES detectors) in total. The first two detector arrays, observing at 146 GHz, were deployed in 2013 and 2014, respectively. The third and final array is composed of multichroic pixels sensitive to both 90 and 146 GHz and saw first light in February 2015. Fabricated at NIST, this dichroic array consists of 255 pixels, with a total of 1020 polarization sensitive bolometers and is coupled to the telescope with a monolithic array of broad-band silicon feedhorns. The detectors are read out using time-division SQUID multiplexing and cooled by a dilution refrigerator at 110 mK. We present an overview of the assembly and characterization of this multichroic array in the lab, and the initial detector performance in Chile. The detector array has a TES detector electrical yield of 85 %, a total array sensitivity of less than 10 \\upmu K√{ {s}}, and detector time constants and saturation powers suitable for ACT CMB observations.

  5. Radiation detection at very low temperature. DRTBT 1992 -Londe-Les-Maures - Course collection

    International Nuclear Information System (INIS)

    Bellefon, A. de; Serra, Guy; Broniatowski, A.; Giraud-Heraud, Y.; Bruere Dawson, R.; Waysand, G.; Maneval, J.P.; Jacquier, B.; Leotin, J.; Chapellier, M.; Beaudin, G.; Encrenaz, P.; Gheudin, M.; Lamarre, J.M.; Ravex, A.; Godfrin, H.; Bret, J.L.; Gianese, Chr.; Torre, J.P.; Marcillac, P. de; Benoit, A.; Jegoudez, G.; Pari, P.

    1992-09-01

    The contributions addressed various themes: Cooled sensors, what are they for? (Search for rare events; Astrophysics, X rays and infrared, Spectrometry in nuclear physics); Cooled sensors (Bolometer physics, Bolometers for photometry, Bolometers for particle detection, Superconducting sensors, Other types of bolometers, Low temperature luminescence, Photo-conductors and photovoltaic BIB, Ionisation at very low temperature, Heterodyne detection); Problems related to the signal (Photometry and external measurement noise, Line, amplification and signal processing), Pulse measurement (Line and amplification, Signal processing), Cryogenics (Cryogenic machines, Very low temperature cryogenics, Noise and environment). Nota: contributions are printed in a different order than they are listed in the table of contents

  6. Phase transition in a modified square Josephson-junction array

    CERN Document Server

    Han, J

    1999-01-01

    We study the phase transition in a modified square proximity-coupled Josephson-junction array with small superconducting islands at the center of each plaquette. We find that the modified square array undergoes a Kosterlitz-Thouless-Berezinskii-like phase transition, but at a lower temperature than the simple square array with the same single-junction critical current. The IV characteristics, as well as the phase transition, resemble qualitatively those of a disordered simple square array. The effects of the presence of the center islands in the modified square array are discussed.

  7. A superconducting magnetic gear

    International Nuclear Information System (INIS)

    Campbell, A M

    2016-01-01

    A comparison is made between a magnetic gear using permanent magnets and superconductors. The objective is to see if there are any fundamental reasons why superconducting magnets should not provide higher power densities than permanent magnets. The gear is based on the variable permeability design of Attilah and Howe (2001 IEEE Trans. Magn. 37 2844–46) in which a ring of permanent magnets surrounding a ring of permeable pole pieces with a different spacing gives an internal field component at the beat frequency. Superconductors can provide much larger fields and forces but will saturate the pole pieces. However the gear mechanism still operates, but in a different way. The magnetisation of the pole pieces is now constant but rotates with angle at the beat frequency. The result is a cylindrical Halbach array which produces an internal field with the same symmetry as in the linear regime, but has an analytic solution. In this paper a typical gear system is analysed with finite elements using FlexPDE. It is shown that the gear can work well into the saturation regime and that the Halbach array gives a good approximation to the results. Replacing the permanent magnets with superconducting tapes can give large increases in torque density, and for something like a wind turbine a combined gear and generator is possible. However there are major practical problems. Perhaps the most fundamental is the large high frequency field which is inevitably present and which will cause AC losses. Also large magnetic fields are required, with all the practical problems of high field superconducting magnets in rotating machines. Nevertheless there are ways of mitigating these difficulties and it seems worthwhile to explore the possibilities of this technology further. (paper)

  8. Ruthenium oxide resistors as sensitive elements of composite bolometers

    International Nuclear Information System (INIS)

    Benassai, M.; Gallinaro, G.; Gatti, F.; Siri, S.; Vitale, S.

    1988-01-01

    Bolometers for particle detection made with Ruthenium oxide thermistors could be produced by means of a simple technique on a variety of different materials as substrata. Preliminary results on alpha particle detection with devices realized using commercial RuO 2 thick film resistor (Tfr) are considered positive for devices operating between. 3 and .1 k and determined us to pursue further the idea. Ruthenium oxide resistors on sapphire at the moment are being prepared. The behaviour of these devices st temperatures lower than .1 k has to be investigated in more detail

  9. Imaging of current distributions in superconducting thin film structures

    International Nuclear Information System (INIS)

    Doenitz, D.

    2006-01-01

    Local analysis plays an important role in many fields of scientific research. However, imaging methods are not very common in the investigation of superconductors. For more than 20 years, Low Temperature Scanning Electron Microscopy (LTSEM) has been successfully used at the University of Tuebingen for studying of condensed matter phenomena, especially of superconductivity. In this thesis LTSEM was used for imaging current distributions in different superconducting thin film structures: - Imaging of current distributions in Josephson junctions with ferromagnetic interlayer, also known as SIFS junctions, showed inhomogeneous current transport over the junctions which directly led to an improvement in the fabrication process. An investigation of improved samples showed a very homogeneous current distribution without any trace of magnetic domains. Either such domains were not present or too small for imaging with the LTSEM. - An investigation of Nb/YBCO zigzag Josephson junctions yielded important information on signal formation in the LTSEM both for Josephson junctions in the short and in the long limit. Using a reference junction our signal formation model could be verified, thus confirming earlier results on short zigzag junctions. These results, which could be reproduced in this work, support the theory of d-wave symmetry in the superconducting order parameter of YBCO. Furthermore, investigations of the quasiparticle tunneling in the zigzag junctions showed the existence of Andreev bound states, which is another indication of the d-wave symmetry in YBCO. - The LTSEM study of Hot Electron Bolometers (HEB) allowed the first successful imaging of a stable 'Hot Spot', a self-heating region in HEB structures. Moreover, the electron beam was used to induce an - otherwise unstable - hot spot. Both investigations yielded information on the homogeneity of the samples. - An entirely new method of imaging the current distribution in superconducting interference devices

  10. Readout of a 176 pixel FDM system for SAFARI TES arrays

    Science.gov (United States)

    Hijmering, R. A.; den Hartog, R.; Ridder, M.; van der Linden, A. J.; van der Kuur, J.; Gao, J. R.; Jackson, B.

    2016-07-01

    In this paper we present the results of our 176-pixel prototype of the FDM readout system for SAFARI, a TES-based focal-plane instrument for the far-IR SPICA mission. We have implemented the knowledge obtained from the detailed study on electrical crosstalk reported previously. The effect of carrier leakage is reduced by a factor two, mutual impedance is reduced to below 1 nH and mutual inductance is removed. The pixels are connected in stages, one quarter of the array half of the array and the full array, to resolve intermediate technical issues. A semi-automated procedure was incorporated to find all optimal settings for all pixels. And as a final step the complete array has been connected and 132 pixels have been read out simultaneously within the frequency range of 1-3.8MHz with an average frequency separation of 16kHz. The noise was found to be detector limited and was not affected by reading out all pixels in a FDM mode. With this result the concept of using FDM for multiplexed bolometer read out for the SAFARI instrument has been demonstrated.

  11. THE RADIO-2 mm SPECTRAL INDEX OF THE CRAB NEBULA MEASURED WITH GISMO

    International Nuclear Information System (INIS)

    Arendt, R. G.; George, J. V.; Staguhn, J. G.; Benford, D. J.; Fixsen, D. J.; Maher, S. F.; Moseley, S. H.; Sharp, E.; Wollack, E. J.; Devlin, M. J.; Dicker, S. R.; Korngut, P. M.; Irwin, K. D.; Jhabvala, C. A.; Miller, T. M.; Kovacs, A.; Mason, B. S.; Navarro, S.; Sievers, A.; Sievers, J. L.

    2011-01-01

    We present results of 2 mm observations of the Crab Nebula, obtained using the Goddard-IRAM Superconducting 2 Millimeter Observer (GISMO) bolometer camera on the IRAM 30 m telescope. Additional 3.3 mm observations with the MUSTANG bolometer array on the Green Bank Telescope are also presented. The integrated 2 mm flux density of the Crab Nebula provides no evidence for the emergence of a second synchrotron component that has been proposed. It is consistent with the radio power-law spectrum, extrapolated up to a break frequency of log (ν b [GHz]) = 2.84 ± 0.29 or ν b = 695 +651 -336 GHz. The Crab Nebula is well resolved by the ∼16.''7 beam (FWHM) of GISMO. Comparison to radio data at comparable spatial resolution enables us to confirm significant spatial variation of the spectral index between 21 cm and 2 mm. The main effect is a spectral flattening in the inner region of the Crab Nebula, correlated with the toroidal structure at the center of the nebula that is prominent in the near-IR through X-ray regime.

  12. Optimization of a bolometer detector for ITER based on Pt absorber on SiN membrane

    Energy Technology Data Exchange (ETDEWEB)

    Meister, H.; Eich, T.; Endstrasser, N.; Giannone, L.; Kannamueller, M.; Kling, A.; Koll, J.; Trautmann, T. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstr. 2, D-85748 Garching (Germany); Detemple, P.; Schmitt, S. [Institut fuer Mikrotechnik Mainz GmbH, Carl-Zeiss-Str. 18-20, D-55129 Mainz (Germany); Collaboration: ASDEX Upgrade Team

    2010-10-15

    Any plasma diagnostic in ITER must be able to operate at temperatures in excess of 200 deg. C and neutron loads corresponding to 0.1 dpa over its lifetime. To achieve this aim for the bolometer diagnostic, a miniaturized metal resistor bolometer detector based on Pt absorbers galvanically deposited on SiN membranes is being developed. The first two generations of detectors featured up to 4.5 {mu}m thick absorbers. Results from laboratory tests are presented characterizing the dependence of their calibration constants under thermal loads up to 450 deg. C. Several detectors have been tested in ASDEX Upgrade providing reliable data but also pointing out the need for further optimization. A laser trimming procedure has been implemented to reduce the mismatch in meander resistances below 1% for one detector and the thermal drifts from this mismatch.

  13. Optimization of a bolometer detector for ITER based on Pt absorber on SiN membranea)

    Science.gov (United States)

    Meister, H.; Eich, T.; Endstrasser, N.; Giannone, L.; Kannamüller, M.; Kling, A.; Koll, J.; Trautmann, T.; ASDEX Upgrade Team; Detemple, P.; Schmitt, S.

    2010-10-01

    Any plasma diagnostic in ITER must be able to operate at temperatures in excess of 200 °C and neutron loads corresponding to 0.1 dpa over its lifetime. To achieve this aim for the bolometer diagnostic, a miniaturized metal resistor bolometer detector based on Pt absorbers galvanically deposited on SiN membranes is being developed. The first two generations of detectors featured up to 4.5 μm thick absorbers. Results from laboratory tests are presented characterizing the dependence of their calibration constants under thermal loads up to 450 °C. Several detectors have been tested in ASDEX Upgrade providing reliable data but also pointing out the need for further optimization. A laser trimming procedure has been implemented to reduce the mismatch in meander resistances below 1% for one detector and the thermal drifts from this mismatch.

  14. Superconducting heterostructures: from antipinning to pinning potentials

    International Nuclear Information System (INIS)

    Carreira, S J; Chiliotte, C; Bekeris, V; Rosen, Y J; Monton, C; Schuller, Ivan K

    2014-01-01

    We study vortex lattice dynamics in a heterostructure that combines two type-II superconductors: a niobium film and a dense triangular array of submicrometric vanadium (V) pillars. Magnetic ac susceptibility measurements reveal a sudden increase in ac penetration, related to an increase in vortex mobility above a magnetic field, H ∗ (T), that decreases linearly with temperature. Additionally, temperature independent matching effects that occur when the number of vortices in the sample is an integer of the number of V pillars, strongly reduce vortex mobility, and were observed for the first and second matching fields, H 1 and H 2 . The angular dependence of H 1 , H 2 and H ∗ (T) shows that matching is determined by the normal applied field component, while H ∗ (T) is independent of the applied field orientation. This important result identifies H ∗ (T) with the critical field boundary for the normal to superconducting transition of V pillars. Below H ∗ (T), superconducting V pillars repel vortices, and the array becomes an ‘antipinning’ landscape that is more effective in reducing vortex mobility than the ‘pinning’ landscape of the normal V sites above H ∗ (T). Matching effects are observed both below and above H ∗ (T), implying the presence of ordered vortex configurations for ‘antipinning’ or ‘pinning’ arrays. (paper)

  15. Chiral classical states in a rhombus and a rhombi chain of Josephson junctions with two-band superconducting elements

    CERN Document Server

    Dias, R G; Coutinho, B C; Martins, L P

    2014-01-01

    We present a study of Josephson junctions arrays with two-band superconducting elements in the highcapacitance limit. We consider two particular geometries for these arrays: a single rhombus and a rhombi chain with two-band superconducting elements at the spinal positions. We show that the rhombus shaped JJ circuit and the rhombi chain can be mapped onto a triangular JJ circuit and a JJ two-leg ladder, respectively, with zero effective magnetic flux, but with Josephson couplings that are magnetic flux dependent. If the two-band superconductors are in a sign-reversed pairing state, one observes transitions to or from chiral phase configurations in the mapped superconducting arrays when magnetic flux or temperature are varied. The phase diagram for these chiral configurations is discussed. When half-flux quantum threads each rhombus plaquette, new phase configurations of the rhombi chain appear that are characterized by the doubling of the periodicity of the energy density along the chain, with every other two-...

  16. Assembly, characterization, and operation of large-scale TES detector arrays for ACTPol

    Science.gov (United States)

    Pappas, Christine Goodwin

    2016-01-01

    The Polarization-sensitive Receiver for the Atacama Cosmology Telescope (ACTPol) is designed to measure the Cosmic Microwave Background (CMB) temperature and polarization anisotropies on small angular scales. Measurements of the CMB temperature and polarization anisotropies have produced arguably the most important cosmological data to date, establishing the LambdaCDM model and providing the best constraints on most of its parameters. To detect the very small fluctuations in the CMB signal across the sky, ACTPol uses feedhorn-coupled Transition-Edge Sensor (TES) detectors. A TES is a superconducting thin film operated in the transition region between the superconducting and normal states, where it functions as a highly sensitive resistive thermometer. In this thesis, aspects of the assembly, characterization, and in-field operation of the ACTPol TES detector arrays are discussed. First, a novel microfabrication process for producing high-density superconducting aluminum/polyimide flexible circuitry (flex) designed to connect large-scale detector arrays to the first stage of readout is presented. The flex is used in parts of the third ACTPol array and is currently being produced for use in the AdvACT detector arrays, which will begin to replace the ACTPol arrays in 2016. Next, we describe methods and results for the in-lab and on-telescope characterization of the detectors in the third ACTPol array. Finally, we describe the ACTPol TES R(T,I) transition shapes and how they affect the detector calibration and operation. Methods for measuring the exact detector calibration and re-biasing functions, taking into account the R(T,I) transition shape, are presented.

  17. Characterizing Ensembles of Superconducting Qubits

    Science.gov (United States)

    Sears, Adam; Birenbaum, Jeff; Hover, David; Rosenberg, Danna; Weber, Steven; Yoder, Jonilyn L.; Kerman, Jamie; Gustavsson, Simon; Kamal, Archana; Yan, Fei; Oliver, William

    We investigate ensembles of up to 48 superconducting qubits embedded within a superconducting cavity. Such arrays of qubits have been proposed for the experimental study of Ising Hamiltonians, and efficient methods to characterize and calibrate these types of systems are still under development. Here we leverage high qubit coherence (> 70 μs) to characterize individual devices as well as qubit-qubit interactions, utilizing the common resonator mode for a joint readout. This research was funded by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA) under Air Force Contract No. FA8721-05-C-0002. The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of ODNI, IARPA, or the US Government.

  18. Sea level characterization of a 1100 g sapphire bolometer

    CERN Document Server

    Pécourt, S; Bobin, C; Coron, N; Jesus, M D; Hadjout, J P; Leblanc, J W; Marcillac, P D

    1999-01-01

    A first characterization of a 1100 g sapphire bolometer, performed at sea level and at a working temperature of 40 mK, is presented. Despite perturbations coming from the high-radioactive background and cosmic rays, calibration spectra could be achieved with an internal alpha source and a sup 5 sup 7 Co gamma-ray source: the experimental threshold is 25 keV, while the FWHM resolution is 17.4 keV for the 122 keV peak. Possible heat release effects are discussed, and a new limit of 9x10 sup - sup 1 sup 4 W/g is obtained for sapphire.

  19. Inductive Shimming of Superconductive Undulators - Preparations for a realistic test

    CERN Document Server

    Schoerling, D; Bernhard,; Burkart, F; Ehlers, S; Gerstl, S; Grau, A; Peiffer, P; Rossmanith, R; Wollmann, D

    2010-01-01

    The monochromaticity and intensity of synchrotron light emitted by undulators strongly depend on the undulator field quality. For the particular case of superconductive undulators it was shown recently that their field quality can be significantly improved by an array of coupled high temperature superconductor loops attached to the surface of the superconductive undulator. Local field errors induce currents in the coupled closed superconducting loops and, as a result, the hereby generated magnetic field minimizes the field errors. In previous papers the concept was described theoretically and a proof-of-principle experiment was reported. This paper reports on a prepatation experiment for the first quantitative measurement of the phase error reduction in a 13-period short model undulator equipped with a full-scale induction shimming system.

  20. Improvements in 130Te double beta decay search with cryogenic TeO2 array detectors

    International Nuclear Information System (INIS)

    Alessandrello, A.; Brofferio, C.; Bucci, C.; Caspani, P.; Cremonesi, O.; Fiorini, E.; Giuliani, A.; Nucciotti, A.; Pavan, M.; Pessina, G.; Previtali, E.; Zanotti, L.

    1996-01-01

    Single crystal TeO 2 bolometers have been used since 5 years ago to search for neutrinoless DBD of 130 Te. During the last year, our group has been studying and preparing the first array of 4 crystals, 340 g each, opening this technique to new frontiers in rare events' physics. The results and perspectives of this second generation cryogenic detectors are here reported and discussed, with particular emphasis on the peculiarities which make them feasible for a consistent upgrading of our previous result in DBD search. (orig.)

  1. The Physics of Superconducting Microwave Resonators

    Science.gov (United States)

    Gao, Jiansong

    Over the past decade, low temperature detectors have brought astronomers revolutionary new observational capabilities and led to many great discoveries. Although a single low temperature detector has very impressive sensitivity, a large detector array would be much more powerful and are highly demanded for the study of more difficult and fundamental problems in astronomy. However, current detector technologies, such as transition edge sensors and superconducting tunnel junction detectors, are difficult to integrate into a large array. The microwave kinetic inductance detector (MKID) is a promising new detector technology invented at Caltech and JPL which provides both high sensitivity and an easy solution to the detector integration. It senses the change in the surface impedance of a superconductor as incoming photons break Cooper pairs, by using high-Q superconducting microwave resonators capacitively coupled to a common feedline. This architecture allows thousands of detectors to be easily integrated through passive frequency domain multiplexing. In this thesis, we explore the rich and interesting physics behind these superconducting microwave resonators. The first part of the thesis discusses the surface impedance of a superconductor, the kinetic inductance of a superconducting coplanar waveguide, and the circuit response of a resonator. These topics are related with the responsivity of MKIDs. The second part presents the study of the excess frequency noise that is universally observed in these resonators. The properties of the excess noise, including power, temperature, material, and geometry dependence, have been quantified. The noise source has been identified to be the two-level systems in the dielectric material on the surface of the resonator. A semi-empirical noise model has been developed to explain the power and geometry dependence of the noise, which is useful to predict the noise for a specified resonator geometry. The detailed physical noise

  2. A superconducting large-angle magnetic suspension. Final report

    International Nuclear Information System (INIS)

    Downer, J.R.; Anastas, G.V. Jr.; Bushko, D.A.; Flynn, F.J.; Goldie, J.H.; Gondhalekar, V.; Hawkey, T.J.; Hockney, R.L.; Torti, R.P.

    1992-12-01

    SatCon Technology Corporation has completed a Small Business Innovation Research (SBIR) Phase 2 program to develop a Superconducting Large-Angle Magnetic Suspension (LAMS) for the NASA Langley Research Center. The Superconducting LAMS was a hardware demonstration of the control technology required to develop an advanced momentum exchange effector. The Phase 2 research was directed toward the demonstration for the key technology required for the advanced concept CMG, the controller. The Phase 2 hardware consists of a superconducting solenoid ('source coils') suspended within an array of nonsuperconducting coils ('control coils'), a five-degree-of-freedom positioning sensing system, switching power amplifiers, and a digital control system. The results demonstrated the feasibility of suspending the source coil. Gimballing (pointing the axis of the source coil) was demonstrated over a limited range. With further development of the rotation sensing system, enhanced angular freedom should be possible

  3. Final Scientific/Technical Report: Electronics for Large Superconducting Tunnel Junction Detector Arrays for Synchrotron Soft X-ray Research

    Energy Technology Data Exchange (ETDEWEB)

    Warburton, William K

    2009-03-06

    Superconducting tunnel junction (STJ) detectors offer a an approach to detecting soft x-rays with energy resolutions 4-5 times better and at rates 10 faster than traditions semiconductor detectors. To make such detectors feasible, however, then need to be deployed in large arrays of order 1000 detectors, which in turn implies that their processing electronics must be compact, fully computer controlled, and low cost per channel while still delivering ultra-low noise performance so as to not degrade the STJ's performance. We report on our progress in designing a compact, low cost preamplifier intended for this application. In particular, we were able to produce a prototype preamplifier of 2 sq-cm area and a parts cost of less than $30 that matched the energy resolution of the best conventional system to date and demonstrated its ability to acquire an STJ I-V curve under computer control, the critical step for determining and setting the detectors' operating points under software control.

  4. A new method for background rejection with surface sensitive bolometers

    International Nuclear Information System (INIS)

    Nones, C.; Foggetta, L.; Giuliani, A.; Pedretti, M.; Salvioni, C.; Sangiorgio, S.

    2006-01-01

    We report the performance of three prototype TeO 2 macrobolometers, able to identify events due to energy deposited at the detector surface. This capability is obtained by thermally coupling thin active layers to the main absorber of the bolometer, and is proved by irradiating the detectors with alpha particles. This technique can be very useful in view of background study and reduction for the CUORE experiment, a next generation Double Beta Decay search based on TeO 2 macrobolometers and to be installed in the Laboratori Nazionali del Gran Sasso

  5. European roadmap on superconductive electronics - status and perspectives

    Science.gov (United States)

    Anders, S.; Blamire, M. G.; Buchholz, F.-Im.; Crété, D.-G.; Cristiano, R.; Febvre, P.; Fritzsch, L.; Herr, A.; Il'ichev, E.; Kohlmann, J.; Kunert, J.; Meyer, H.-G.; Niemeyer, J.; Ortlepp, T.; Rogalla, H.; Schurig, T.; Siegel, M.; Stolz, R.; Tarte, E.; ter Brake, H. J. M.; Toepfer, H.; Villegier, J.-C.; Zagoskin, A. M.; Zorin, A. B.

    2010-12-01

    many other applications SQUIDs are used as sensors for magnetic heart and brain signals in medical applications, as sensor for geological surveying and food-processing and for non-destructive testing. As amplifiers of electrical signals, SQUIDs can nearly reach the theoretical limit given by Quantum Mechanics. A further important field of application is the detection of very weak signals by ‘transition-edge’ bolometers, superconducting nanowire single-photon detectors, and superconductive tunnel junctions. Their application as radiation detectors in a wide frequency range, from microwaves to X-rays is now standard. The very low losses of superconductors have led to commercial microwave filter designs that are now widely used in the USA in base stations for cellular phones and in military communication applications. The number of demonstrated applications is continuously increasing and there is no area in professional electronics, in which superconductive electronics cannot be applied and surpasses the performance of classical devices. Superconductive electronics has to be cooled to very low temperatures. Whereas this was a bottleneck in the past, cooling techniques have made a huge step forward in recent years: very compact systems with high reliability and a wide range of cooling power are available commercially, from microcoolers of match-box size with milli-Watt cooling power to high-reliability coolers of many Watts of cooling power for satellite applications. Superconductive electronics will not replace semiconductor electronics and similar room-temperature techniques in standard applications, but for those applications which require very high speed, low-power consumption, extreme sensitivity or extremely high precision, superconductive electronics is superior to all other available techniques. To strengthen the European competitiveness in superconductor electronics research projects have to be set-up in the following field: Ultra-sensitive sensing and imaging

  6. Superconductivity

    International Nuclear Information System (INIS)

    Palmieri, V.

    1990-01-01

    This paper reports on superconductivity the absence of electrical resistance has always fascinated the mind of researchers with a promise of applications unachievable by conventional technologies. Since its discovery superconductivity has been posing many questions and challenges to solid state physics, quantum mechanics, chemistry and material science. Simulations arrived to superconductivity from particle physics, astrophysic, electronics, electrical engineering and so on. In seventy-five years the original promises of superconductivity were going to become reality: a microscopical theory gave to superconductivity the cloth of the science and the level of technological advances was getting higher and higher. High field superconducting magnets became commercially available, superconducting electronic devices were invented, high field accelerating gradients were obtained in superconductive cavities and superconducting particle detectors were under study. Other improvements came in a quiet progression when a tornado brought a revolution in the field: new materials had been discovered and superconductivity, from being a phenomenon relegated to the liquid Helium temperatures, became achievable over the liquid Nitrogen temperature. All the physics and the technological implications under superconductivity have to be considered ab initio

  7. Novel Magnetically-Tuned TES For Imaging X-ray Spectroscopy Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Superconducting transition-edge sensors (TESs) are the state-of-the art technology for microcalorimeter and bolometer applications across the electromagnetic...

  8. Design and simulation of superconducting Lorentz Force Electrical Impedance Tomography (LFEIT)

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Boyang, E-mail: bs506@cam.ac.uk; Fu, Lin, E-mail: lf359@cam.ac.uk; Geng, Jianzhao, E-mail: jg717@cam.ac.uk; Zhang, Xiuchang, E-mail: xz326@cam.ac.uk; Zhang, Heng, E-mail: hz301@cam.ac.uk; Dong, Qihuan, E-mail: qd210@cam.ac.uk; Li, Chao, E-mail: cl644@cam.ac.uk; Li, Jing, E-mail: jl908@cam.ac.uk; Coombs, T.A., E-mail: tac1000@cam.ac.uk

    2016-05-15

    Highlights: • Design of superconducting magnets using Halbach Array configuration. • Combination of superconducting magnets together with Lorentz Force Electrical Impedance Tomography (LFEIT) system. • Simulation of superconducting LFEIT system based on the theory of magneto-acoustic effect. - Abstract: Lorentz Force Electrical Impedance Tomography (LFEIT) is a hybrid diagnostic scanner with strong capability for biological imaging, particularly in cancer and haemorrhages detection. This paper presents the design and simulation of a novel combination: a superconducting magnet together with LFEIT system. Superconducting magnets can generate magnetic field with high intensity and homogeneity, which could significantly enhance the imaging performance. The modelling of superconducting magnets was carried out using Finite Element Method (FEM) package, COMSOL Multiphysics, which was based on Partial Differential Equation (PDE) model with H-formulation coupling B-dependent critical current density and bulk approximation. The mathematical model for LFEIT system was built based on the theory of magneto-acoustic effect. The magnetic field properties from magnet design were imported into the LFEIT model. The basic imaging of electrical signal was developed using MATLAB codes. The LFEIT model simulated two samples located in three different magnetic fields with varying magnetic strength and homogeneity.

  9. Superconducting states and depinning transitions of Josephson ladders

    International Nuclear Information System (INIS)

    Barahona, M.; Strogatz, S.H.; Orlando, T.P.

    1998-01-01

    We present analytical and numerical studies of pinned superconducting states of open-ended Josephson ladder arrays, neglecting inductances but taking edge effects into account. Treating the edge effects perturbatively, we find analytical approximations for three of these superconducting states emdash the no-vortex, fully frustrated, and single-vortex states emdash as functions of the dc bias current I and the frustration f. Bifurcation theory is used to derive formulas for the depinning currents and critical frustrations at which the superconducting states disappear or lose dynamical stability as I and f are varied. These results are combined to yield a zero-temperature stability diagram of the system with respect to I and f. To highlight the effects of the edges, we compare this dynamical stability diagram to the thermodynamic phase diagram for the infinite system where edges have been neglected. We briefly indicate how to extend our methods to include self-inductances. copyright 1998 The American Physical Society

  10. Graphene-based mid-infrared room-temperature pyroelectric bolometers with ultrahigh temperature coefficient of resistance.

    Science.gov (United States)

    Sassi, U; Parret, R; Nanot, S; Bruna, M; Borini, S; De Fazio, D; Zhao, Z; Lidorikis, E; Koppens, F H L; Ferrari, A C; Colli, A

    2017-01-31

    There is a growing number of applications demanding highly sensitive photodetectors in the mid-infrared. Thermal photodetectors, such as bolometers, have emerged as the technology of choice, because they do not need cooling. The performance of a bolometer is linked to its temperature coefficient of resistance (TCR, ∼2-4% K -1 for state-of-the-art materials). Graphene is ideally suited for optoelectronic applications, with a variety of reported photodetectors ranging from visible to THz frequencies. For the mid-infrared, graphene-based detectors with TCRs ∼4-11% K -1 have been demonstrated. Here we present an uncooled, mid-infrared photodetector, where the pyroelectric response of a LiNbO 3 crystal is transduced with high gain (up to 200) into resistivity modulation for graphene. This is achieved by fabricating a floating metallic structure that concentrates the pyroelectric charge on the top-gate capacitor of the graphene channel, leading to TCRs up to 900% K -1 , and the ability to resolve temperature variations down to 15 μK.

  11. dc properties of series-parallel arrays of Josephson junctions in an external magnetic field

    International Nuclear Information System (INIS)

    Lewandowski, S.J.

    1991-01-01

    A detailed dc theory of superconducting multijunction interferometers has previously been developed by several authors for the case of parallel junction arrays. The theory is now extended to cover the case of a loop containing several junctions connected in series. The problem is closely associated with high-T c superconductors and their clusters of intrinsic Josephson junctions. These materials exhibit spontaneous interferometric effects, and there is no reason to assume that the intrinsic junctions form only parallel arrays. A simple formalism of phase states is developed in order to express the superconducting phase differences across the junctions forming a series array as functions of the phase difference across the weakest junction of the system, and to relate the differences in critical currents of the junctions to gaps in the allowed ranges of their phase functions. This formalism is used to investigate the energy states of the array, which in the case of different junctions are split and separated by energy barriers of height depending on the phase gaps. Modifications of the washboard model of a single junction are shown. Next a superconducting inductive loop containing a series array of two junctions is considered, and this model is used to demonstrate the transitions between phase states and the associated instabilities. Finally, the critical current of a parallel connection of two series arrays is analyzed and shown to be a multivalued function of the externally applied magnetic flux. The instabilities caused by the presence of intrinsic serial junctions in granular high-T c materials are pointed out as a potential source of additional noise

  12. Packaging and interconnection for superconductive circuitry

    International Nuclear Information System (INIS)

    Anacker, W.

    1976-01-01

    A three dimensional microelectronic module packaged for reduced signal propagation delay times including a plurality of circuit carrying means, which may comprise unbacked chips, with integrated superconductive circuitry thereon is described. The circuit carrying means are supported on their edges and have contact lands in the vicinity of, or at, the edges to provide for interconnecting circuitry. The circuit carrying means are supported by supporting means which include slots to provide a path for interconnection wiring to contact the lands of the circuit carrying means. Further interconnecting wiring may take the form of integrated circuit wiring on the reverse side of the supporting means. The low heat dissipation of the superconductive circuitry allows the circuit carrying means to be spaced approximately no less than 30 mils apart. The three dimensional arrangement provides lower random propagation delays than would a planar array of circuits

  13. Instanton glass generated by noise in a Josephson-junction array.

    Science.gov (United States)

    Chudnovsky, E M

    2009-09-25

    We compute the correlation function of a superconducting order parameter in a continuous model of a two-dimensional Josephson-junction array in the presence of a weak Gaussian noise. When the Josephson coupling is large compared to the charging energy, the correlations in the Euclidian space decay exponentially at low temperatures regardless of the strength of the noise. We interpret such a state as a collective Cooper-pair insulator and argue that it resembles properties of disordered superconducting films.

  14. Superconductivity

    CERN Document Server

    Thomas, D B

    1974-01-01

    A short general review is presented of the progress made in applied superconductivity as a result of work performed in connection with the high-energy physics program in Europe. The phenomenon of superconductivity and properties of superconductors of Types I and II are outlined. The main body of the paper deals with the development of niobium-titanium superconducting magnets and of radio-frequency superconducting cavities and accelerating structures. Examples of applications in and for high-energy physics experiments are given, including the large superconducting magnet for the Big European Bubble Chamber, prototype synchrotron magnets for the Super Proton Synchrotron, superconducting d.c. beam line magnets, and superconducting RF cavities for use in various laboratories. (0 refs).

  15. Melt formed superconducting joint between superconducting tapes

    International Nuclear Information System (INIS)

    Benz, M.G.; Knudsen, B.A.; Rumaner, L.E.; Zaabala, R.J.

    1992-01-01

    This patent describes a superconducting joint between contiguous superconducting tapes having an inner laminate comprised of a parent-metal layer selected from the group niobium, tantalum, technetium, and vanadium, a superconductive intermetallic compound layer on the parent-metal layer, a reactive-metal layer that is capable of combining with the parent-metal and forming the superconductive intermetallic compound, the joint comprising: a continuous precipitate of the superconductive intermetallic compound fused to the tapes forming a continuous superconducting path between the tapes

  16. Radiation detection at very low temperature. DRTBT 2009, Frejus - Course collection

    International Nuclear Information System (INIS)

    Camus, Ph.; Hoffmann, Ch.; Monfardini, A.; Camus, P.; Marcillac, P. de; Broniatowski, A.; Marnieros, S.; Dumoulin, L.; Rodriguez, L.; Rodrigues, Matias; Desert, F.-Xavier; Villegier, J.-C.; Prele, Damien; Sauvageot, J.-L.; Pigot, Claude; Korte, Piet de; Rich, J.; Juillard, A.; Nonez, C.; Jin, Yong; Gascon, J.; Pari, P.; Luchier, N.; Hamilton, J.-Ch.; Chardin, G.

    2009-05-01

    This document gathers Power Point presentations. After a general introduction, the following topics have been addressed during the first day: Elementary excitations, Physics of Anderson insulators, Thermal detectors, Silicon technology and Si-doped detectors, Magnetic bolometers, Principle and perspectives of KIDs (Kinetic Inductance Detectors). The second day dealt with FIR and millimetre astronomy: Stakes, Millimetre and sub-millimetre optics, Bolometer matrices for millimetre astrophysics, Superconductivity and cryogenic detection, Hot electron bolometers (HEB) as examples of superconducting junction, Low noise electronics for high impedance sensor, Squids and multiplexing techniques. The topic of the third day was X rays. The contributions dealt with: the IXO mission with micro-calorimeters based on Si detectors for X ray detection, TES detectors for X-rays astrophysics. The fourth day was dedicated to the detection of rare events (dark matter, 2 beta, neutrino, and so on). The authors address the following aspects: Cosmology and dark matter, Direct detection of dark matter, Cryogenic detectors R and D for dark matter, New perspectives in electronics for bolometers, Signal processing, Dilution-based cryostats for instrumentation, Cryogenic techniques below 1 K. The contributions presented on the fifth and last day addressed the following issues: Experiment for the measurement of CMB polarisation, Limitations and perspectives of cryogenic detectors

  17. Coupled superconducting resonant cavities for a heavy ion linac

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K W [Argonne National Lab., IL (United States); Roy, A [Nuclear Science Center, New Delhi (India)

    1992-11-01

    A design for a superconducting niobium slow-wave accelerating structure has been explored that may have performance and cost advantages over existing technology. The option considered is an array of pairs of quarter-wave coaxial-line resonant cavities, the two elements of each pair strongly coupled through a short superconducting transmission line. In the linac formed by such an array, each paired structure is independently phased. A disadvantage of two-gap slow wave structures is that each cavity is relatively short, so that a large number of independently-phased elements is required for a linac. Increasing the number of drift tubes per cavity reduces the number of independently-phased elements but at the cost of reducing the range of useful velocity acceptance for each element. Coupling two cavities splits the accelerating rf eigenmode into two resonant modes each of which covers a portion of the full velocity acceptance range of the original, single cavity mode. Using both of these resonant modes makes feasible the use of coupled cavity pairs for a linac with little loss in velocity acceptance. (Author) 2 figs., 8 refs.

  18. Coupled superconducting resonant cavities for a heavy ion linac

    International Nuclear Information System (INIS)

    Shepard, K.W.; Roy, A.

    1992-01-01

    A design for a superconducting niobium slow-wave accelerating structure has been explored that may have performance and cost advantages over existing technology. The option considered is an array of pairs of quarter-wave coaxial-line resonant cavities, the two elements of each pair strongly coupled through a short superconducting transmission line. In the linac formed by such an array, each paired structure is independently phased. A disadvantage of two-gap slow wave structures is that each cavity is relatively short, so that a large number of independently-phased elements is required for a linac. Increasing the number of drift tubes per cavity reduces the number of independently-phased elements but at the cost of reducing the range of useful velocity acceptance for each element. Coupling two cavities splits the accelerating rf eigenmode into two resonant modes each of which covers a portion of the full velocity acceptance range of the original, single cavity mode. Using both of these resonant modes makes feasible the use of coupled cavity pairs for a linac with little loss in velocity acceptance. (Author) 2 figs., 8 refs

  19. A low-power CMOS readout IC design for bolometer applications

    Science.gov (United States)

    Galioglu, Arman; Abbasi, Shahbaz; Shafique, Atia; Ceylan, Ömer; Yazici, Melik; Kaynak, Mehmet; Durmaz, Emre C.; Arsoy, Elif Gul; Gurbuz, Yasar

    2017-02-01

    A prototype of a readout IC (ROIC) designed for use in high temperature coefficient of resistance (TCR) SiGe microbolometers is presented. The prototype ROIC architecture implemented is based on a bridge with active and blind bolometer pixels with a capacitive transimpedance amplifier (CTIA) input stage and column parallel integration with serial readout. The ROIC is designed for use in high (>= 4 %/K) TCR and high detector resistance Si/SiGe microbolometers with 17x17 μm2 pixel sizes in development. The prototype has been designed and fabricated in 0.25- μm SiGe:C BiCMOS process.

  20. Top-Level Simulation of a Smart-Bolometer Using VHDL Modeling

    Directory of Open Access Journals (Sweden)

    Matthieu DENOUAL

    2012-03-01

    Full Text Available An event-driven modeling technique in standard VHDL is presented in this paper for the high level simulation of a resistive bolometer operating in closed-loop mode and implementing smart functions. The closed-loop mode operation is achieved by the capacitively coupled electrical substitution technique. The event-driven VHDL modeling technique is successfully applied to behavioral modeling and simulation of such a multi-physics system involving optical, thermal and electronics mechanisms. The modeling technique allows the high level simulations for the development and validation of the smart functions algorithms of the future integrated smart-device.

  1. Superconducting quantum circuits theory and application

    Science.gov (United States)

    Deng, Xiuhao

    states. The model and toolbox are engineered with a superconducting quantum circuit where two superconducting resonators are coupled via the UQDP circuit. Using fourth order perturbation theory one can realize a complete set of quantum operations between these two photon modes. This helps open a new field to treat photon modes as qubits. Additional, a three-wave mixing scheme using phase qubits permits one to engineer the coupling Hamiltonian using a phase qubit as a tunable coupler. Along with Feynman's idea using quantum to simulate quantum, superconducting quantum simulators have been studied intensively recently. Taking the advantage of mesoscopic size of superconducting circuit and local tunability, we came out the idea to simulate quantum phase transition due to disorder. Our first paper was to propose a superconducting quantum simulator of Bose-Hubbard model to do site-wise manipulation and observe Mott-insulator to superfluid phase transition. The side-band cooling of an array of superconducting resonators is solved after the paper was published. In light of the developed technology in manipulating quantum information with superconducting circuit, one can couple other quantum oscillator system to superconducting resonators in order manipulation of its quantum states or parametric amplification of weak quantum signal. A theory that works for different coupling schemes has been studied in chapter 5. This will be a platform for further research.

  2. Local switching of two-dimensional superconductivity using the ferroelectric field effect

    Science.gov (United States)

    Takahashi, K. S.; Gabay, M.; Jaccard, D.; Shibuya, K.; Ohnishi, T.; Lippmaa, M.; Triscone, J.-M.

    2006-05-01

    Correlated oxides display a variety of extraordinary physical properties including high-temperature superconductivity and colossal magnetoresistance. In these materials, strong electronic correlations often lead to competing ground states that are sensitive to many parameters-in particular the doping level-so that complex phase diagrams are observed. A flexible way to explore the role of doping is to tune the electron or hole concentration with electric fields, as is done in standard semiconductor field effect transistors. Here we demonstrate a model oxide system based on high-quality heterostructures in which the ferroelectric field effect approach can be studied. We use a single-crystal film of the perovskite superconductor Nb-doped SrTiO3 as the superconducting channel and ferroelectric Pb(Zr,Ti)O3 as the gate oxide. Atomic force microscopy is used to locally reverse the ferroelectric polarization, thus inducing large resistivity and carrier modulations, resulting in a clear shift in the superconducting critical temperature. Field-induced switching from the normal state to the (zero resistance) superconducting state was achieved at a well-defined temperature. This unique system could lead to a field of research in which devices are realized by locally defining in the same material superconducting and normal regions with `perfect' interfaces, the interface being purely electronic. Using this approach, one could potentially design one-dimensional superconducting wires, superconducting rings and junctions, superconducting quantum interference devices (SQUIDs) or arrays of pinning centres.

  3. Low temperature composite bolometers using RuO2 films as a thermistor

    International Nuclear Information System (INIS)

    Chapellier, M.; Rasmussen, F.B.

    1989-01-01

    Results from a massive composite bolometer made of a sapphire crystal and ruthenium oxide films are presented. The properties of such RuO 2 films, in the temperature range [50 mK, 200 mK] have been studied. Individual particle detections, using an 241 Am source, have been used to calibrate the system in this temperature interval. Improvements in the performances of such detectors lead to consider them as realistic candidates for the detection of Dark Matter

  4. Progress on axicell MFTF-B superconducting magnet systems

    International Nuclear Information System (INIS)

    Wang, S.T.; Kozman, T.A.; Hanson, C.L.; Shimer, D.W.; VanSant, J.H.; Zbasnik, J.

    1983-01-01

    Since the entire Mirror Fusion Test Facility (MFTF-B) Magnet System was reconfigured from the original A-cell to an axicell design, much progress has been made on the design, fabrication, and installation planning. The axicell MFTF-B magnet array consists of a total of 26 large superconducting main coils. This paper provides an engineering overview of the progress of these coils. Recent studies on the effects of field errors on the plasma at the recircularizing region (transition coils) show that small field errors will generate large displacements of the field lines. These field errors might enhance radial electron heat transport and deteriorate the plasma confinement. Therefore, 16 superconducting trim coils have been designed to correct the coil misalignments. Progress of the trim coils are reported also

  5. Magnetic phenomena in holographic superconductivity with Lifshitz scaling

    Directory of Open Access Journals (Sweden)

    Aldo Dector

    2015-09-01

    Full Text Available We investigate the effects of Lifshitz dynamical critical exponent z on a family of minimal D=4+1 holographic superconducting models, with a particular focus on magnetic phenomena. We see that it is possible to have a consistent Ginzburg–Landau approach to holographic superconductivity in a Lifshitz background. By following this phenomenological approach we are able to compute a wide array of physical quantities. We also calculate the Ginzburg–Landau parameter for different condensates, and conclude that in systems with higher dynamical critical exponent, vortex formation is more strongly unfavored energetically and exhibits a stronger Type I behavior. Finally, following the perturbative approach proposed by Maeda, Natsuume and Okamura, we calculate the critical magnetic field of our models for different values of z.

  6. MgB2 Thin-Film Bolometer for Applications in Far-Infrared Instruments on Future Planetary Missions

    Science.gov (United States)

    Lakew, B.; Aslam, S.; Brasunas, J.; Cao, N.; Costen, N.; La, A.; Stevenson, T.; Waczynski, A.

    2012-01-01

    A SiN membrane based MgB2 thin-film bolometer, with a non-optimized absorber, has been fabricated that shows an electrical noise equivalent power of 256 fW/square root Hz operating at 30 Hz in the 8.5 - 12.35 micron spectral bandpass. This value corresponds to an electrical specific detectivity of 7.6 x 10(exp 10) cm square root Hz/W. The bolometer shows a measured blackbody (optical) specific detectivity of 8.8 x 10(exp 9) cm square root Hz/W, with a responsivity of 701.5 kV/W and a first-order time constant of 5.2 ms. It is predicted that with the inclusion of a gold black absorber that a blackbody specific detectivity of 6.4 x 10(exp 10) cm/square root Hz/W at an operational frequency of 10 Hz, can be realized for integration into future planetary exploration instrumentation where high sensitivity is required in the 17 - 250 micron spectral wavelength range.

  7. Review of superconducting transition-edge sensors for x-ray and gamma-ray spectroscopy

    International Nuclear Information System (INIS)

    Ullom, Joel N; Bennett, Douglas A

    2015-01-01

    We present a review of emerging x-ray and gamma-ray spectrometers based on arrays of superconducting transition-edge sensors (TESs). Special attention will be given to recent progress in TES applications and in understanding TES physics. (paper)

  8. Superconductivity

    CERN Document Server

    Poole, Charles P; Farach, Horacio A

    1995-01-01

    Superconductivity covers the nature of the phenomenon of superconductivity. The book discusses the fundamental principles of superconductivity; the essential features of the superconducting state-the phenomena of zero resistance and perfect diamagnetism; and the properties of the various classes of superconductors, including the organics, the buckministerfullerenes, and the precursors to the cuprates. The text also describes superconductivity from the viewpoint of thermodynamics and provides expressions for the free energy; the Ginzburg-Landau and BCS theories; and the structures of the high

  9. bicep2/ KECK ARRAY . IV. OPTICAL CHARACTERIZATION AND PERFORMANCE OF THE bicep2 AND KECK ARRAY EXPERIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Ade, P.A.R.; Aikin, R.W.; Barkats, D.; Benton, S.J.; Bischoff, C.A.; Bock, J.J.; Bradford, K.J.; Brevik, J.A.; Buder, I.; Bullock, E.; Dowell, C.D.; Duband, L.; Filippini, J.P.; Fliescher, S.; Golwala, S.R.; Halpern, M.; Hasselfield, M.; Hildebrandt, S.R.; Hilton, G.C.; Hui, H.; Irwin, K.D.

    2015-06-18

    bicep2/KECK ARRAY. IV. OPTICAL CHARACTERIZATION AND PERFORMANCE OF THE bicep2 AND KECK ARRAY EXPERIMENTS P. A. R. Ade1, R. W. Aikin2, D. Barkats3, S. J. Benton4, C. A. Bischoff5, J. J. Bock2,6, K. J. Bradford5, J. A. Brevik2, I. Buder5, E. Bullock7Show full author list Published 2015 June 18 • © 2015. The American Astronomical Society. All rights reserved. The Astrophysical Journal, Volume 806, Number 2 Article PDF Figures Tables References Citations 273 Total downloads Cited by 6 articles Turn on MathJax Share this article Get permission to re-use this article Article information Abstract bicep2 and the Keck Array are polarization-sensitive microwave telescopes that observe the cosmic microwave background (CMB) from the South Pole at degree angular scales in search of a signature of inflation imprinted as B-mode polarization in the CMB. bicep2 was deployed in late 2009, observed for three years until the end of 2012 at 150 GHz with 512 antenna-coupled transition edge sensor bolometers, and has reported a detection of B-mode polarization on degree angular scales. The Keck Array was first deployed in late 2010 and will observe through 2016 with five receivers at several frequencies (95, 150, and 220 GHz). bicep2 and the Keck Array share a common optical design and employ the field-proven bicep1 strategy of using small-aperture, cold, on-axis refractive optics, providing excellent control of systematics while maintaining a large field of view. This design allows for full characterization of far-field optical performance using microwave sources on the ground. Here we describe the optical design of both instruments and report a full characterization of the optical performance and beams of bicep2 and the Keck Array at 150 GHz.

  10. Silicon-CsI detector array for heavy-ion reactions

    CERN Document Server

    Norbeck, E; Pogodin, P I; Cheng, Y W; Ingram, F D; Bjarki, O; Grévy, S; Magestro, D J; Molen, A M V; Westfall, G D

    2000-01-01

    An array of 60 silicon-CsI(Tl) detector telescopes has been developed along with associated electronics. The close packing of the telescopes required novel designs for the photodiodes and the silicon DELTA E detectors. Newly developed electronics include preamplifiers, shaping amplifiers, test pulse circuitry, and a module to monitor leakage currents in the silicon diodes. The array covers angles from 5 deg. to 18 deg. in the 4 pi Array at the National Superconducting Cyclotron Laboratory at Michigan State University. It measures protons to 150 MeV and has isotopic resolution for intermediate mass nuclei.

  11. A dual-polarized broadband planar antenna and channelizing filter bank for millimeter wavelengths

    Science.gov (United States)

    O'Brient, Roger; Ade, Peter; Arnold, Kam; Edwards, Jennifer; Engargiola, Greg; Holzapfel, William L.; Lee, Adrian T.; Myers, Michael J.; Quealy, Erin; Rebeiz, Gabriel; Richards, Paul; Suzuki, Aritoki

    2013-02-01

    We describe the design, fabrication, and testing of a broadband log-periodic antenna coupled to multiple cryogenic bolometers. This detector architecture, optimized here for astrophysical observations, simultaneously receives two linear polarizations with two octaves of bandwidth at millimeter wavelengths. The broad bandwidth signal received by the antenna is divided into sub-bands with integrated in-line frequency-selective filters. We demonstrate two such filter banks: a diplexer with two sub-bands and a log-periodic channelizer with seven contiguous sub-bands. These detectors have receiver efficiencies of 20%-40% and percent level polarization isolation. Superconducting transition-edge sensor bolometers detect the power in each sub-band and polarization. We demonstrate circularly symmetric beam patterns, high polarization isolation, accurately positioned bands, and high optical efficiency. The pixel design is applicable to astronomical observations of intensity and polarization at millimeter through sub-millimeter wavelengths. As compared with an imaging array of pixels measuring only one band, simultaneous measurements of multiple bands in each pixel has the potential to result in a higher signal-to-noise measurement while also providing spectral information. This development facilitates compact systems with high mapping speeds for observations that require information in multiple frequency bands.

  12. Development of {sup 100}Mo-containing scintillating bolometers for a high-sensitivity neutrinoless double-beta decay search

    Energy Technology Data Exchange (ETDEWEB)

    Armengaud, E.; Gros, M.; Herve, S.; Magnier, P.; Navick, X.F.; Nones, C.; Paul, B.; Penichot, Y.; Zolotarova, A.S. [Universite Paris-Saclay, IRFU, CEA, Gif-sur-Yvette (France); Augier, C.; Billard, J.; Cazes, A.; Charlieux, F.; Jesus, M. de; Gascon, J.; Juillard, A.; Queguiner, E.; Sanglard, V.; Vagneron, L. [Univ Lyon, Universite Lyon 1, CNRS/IN2P3, IPN-Lyon, Villeurbanne (France); Barabash, A.S.; Konovalov, S.I.; Umatov, V.I. [National Research Centre Kurchatov Institute, Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Beeman, J.W. [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Bekker, T.B. [V.S. Sobolev Institute of Geology and Mineralogy of the Siberian Branch of the RAS, Novosibirsk (Russian Federation); Bellini, F.; Ferroni, F. [Sapienza Universita di Roma, Dipartimento di Fisica, Rome (Italy); INFN, Sezione di Roma, Rome (Italy); Benoit, A.; Camus, P. [CNRS-Neel, Grenoble (France); Berge, L.; Chapellier, M.; Dumoulin, L.; Humbert, V.; Le Sueur, H.; Marcillac, P. de; Marnieros, S.; Marrache-Kikuchi, C.; Novati, V.; Olivieri, E.; Plantevin, O. [CSNSM, Univ. Paris-Sud, CNRS/IN2P3, Universite Paris-Saclay, Orsay (France); Bergmann, T.; Kleifges, M.; Tcherniakhovski, D.; Weber, M. [Karlsruhe Institute of Technology, Institut fuer Prozessdatenverarbeitung und Elektronik, Karlsruhe (Germany); Boiko, R.S.; Danevich, F.A.; Kobychev, V.V.; Nikolaichuk, M.O.; Tretyak, V.I. [Institute for Nuclear Research, Kyiv (Ukraine); Broniatowski, A. [CSNSM, Univ. Paris-Sud, CNRS/IN2P3, Universite Paris-Saclay, Orsay (France); Karlsruhe Institute of Technology, Institut fuer Experimentelle Teilchenphysik, Karlsruhe (Germany); Brudanin, V.; Rozov, S.; Yakushev, E. [JINR, Laboratory of Nuclear Problems, Dubna, Moscow Region (Russian Federation); Capelli, S.; Gironi, L.; Pavan, M.; Pessina, G. [Universita di Milano Bicocca, Dipartimento di Fisica, Milan (Italy); INFN, Sezione di Milano Bicocca, Milan (Italy); Cardani, L.; Casali, N.; Dafinei, I.; Tomei, C.; Vignati, M. [INFN, Sezione di Roma, Rome (Italy); Chernyak, D.M. [Institute for Nuclear Research, Kyiv (Ukraine); The University of Tokyo, Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo Institutes for Advanced Study, Kashiwa, Chiba (Japan); Combarieu, M. de; Pari, P. [Universite Paris-Saclay, IRAMIS, CEA, Gif-sur-Yvette (France); Coron, N.; Redon, T. [Universite Paris-Sud, IAS, CNRS, Orsay (France); Devoyon, L.; Koskas, F.; Strazzer, O. [Universite Paris-Saclay, Orphee, CEA, Gif-sur-Yvette (France); Di Domizio, S. [Universita di Genova, Dipartimento di Fisica, Genoa (Italy); INFN Sezione di Genova, Genoa (Italy); Eitel, K.; Siebenborn, B. [Karlsruhe Institute of Technology, Institut fuer Kernphysik, Karlsruhe (Germany); Enss, C.; Fleischmann, A.; Gastaldo, L. [Heidelberg University, Kirchhoff Institute for Physics, Heidelberg (Germany); Foerster, N.; Kozlov, V. [Karlsruhe Institute of Technology, Institut fuer Experimentelle Teilchenphysik, Karlsruhe (Germany); Giuliani, A. [CSNSM, Univ. Paris-Sud, CNRS/IN2P3, Universite Paris-Saclay, Orsay (France); Universita dell' Insubria, DISAT, Como (Italy); Grigorieva, V.D.; Ivannikova, N.V.; Ivanov, I.M.; Makarov, E.P.; Shlegel, V.N.; Vasiliev, Ya.V. [Nikolaev Institute of Inorganic Chemistry, Novosibirsk (Russian Federation); Hehn, L. [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Karlsruhe Institute of Technology, Institut fuer Kernphysik, Karlsruhe (Germany); Jin, Y. [Laboratoire de Photonique et de Nanostructures, CNRS, Marcoussis (France); Kraus, H. [University of Oxford, Department of Physics, Oxford (United Kingdom); Kudryavtsev, V.A. [University of Sheffield, Department of Physics and Astronomy, Sheffield (United Kingdom); Laubenstein, M.; Nagorny, S.; Pattavina, L.; Pirro, S. [INFN, Laboratori Nazionali del Gran Sasso, Assergi, AQ (Italy); Loidl, M.; Rodrigues, M. [CEA-Saclay, CEA, LIST, Laboratoire National Henri Becquerel (LNE-LNHB), Gif-sur-Yvette Cedex (France); Mancuso, M. [CSNSM, Univ. Paris-Sud, CNRS/IN2P3, Universite Paris-Saclay, Orsay (France); Universita dell' Insubria, DISAT, Como (Italy); Max-Planck-Institut fuer Physik, Munich (Germany); Pagnanini, L.; Schaeffner, K. [INFN, Laboratori Nazionali del Gran Sasso, Assergi, AQ (Italy); INFN, Gran Sasso Science Institute, L' Aquila (Italy); Piperno, G. [INFN, Laboratori Nazionali di Frascati, Rome (Italy); Poda, D.V. [CSNSM, Univ. Paris-Sud, CNRS/IN2P3, Universite Paris-Saclay, Orsay (France); Institute for Nuclear Research, Kyiv (Ukraine); Rusconi, C. [INFN, Laboratori Nazionali del Gran Sasso, Assergi, AQ (Italy); University of South Carolina, Department of Physics and Astronomy, Columbia, SC (United States); Scorza, S. [Karlsruhe Institute of Technology, Institut fuer Experimentelle Teilchenphysik, Karlsruhe (Germany); SNOLAB, Lively, ON (Canada); Velazquez, M. [Universite de Bordeaux, ICMCB, CNRS, Pessac (France)

    2017-11-15

    This paper reports on the development of a technology involving {sup 100}Mo-enriched scintillating bolometers, compatible with the goals of CUPID, a proposed next-generation bolometric experiment to search for neutrinoless double-beta decay. Large mass (∝ 1 kg), high optical quality, radiopure {sup 100}Mo-containing zinc and lithium molybdate crystals have been produced and used to develop high performance single detector modules based on 0.2-0.4 kg scintillating bolometers. In particular, the energy resolution of the lithium molybdate detectors near the Q-value of the double-beta transition of {sup 100}Mo (3034 keV) is 4-6 keV FWHM. The rejection of the α-induced dominant background above 2.6 MeV is better than 8σ. Less than 10 μBq/kg activity of {sup 232}Th({sup 228}Th) and {sup 226}Ra in the crystals is ensured by boule recrystallization. The potential of {sup 100}Mo-enriched scintillating bolometers to perform high sensitivity double-beta decay searches has been demonstrated with only 10 kg x d exposure: the two neutrino double-beta decay half-life of {sup 100}Mo has been measured with the up-to-date highest accuracy as T{sub 1/2} = [6.90 ± 0.15(stat.) ± 0.37(syst.)] x 10{sup 18} years. Both crystallization and detector technologies favor lithium molybdate, which has been selected for the ongoing construction of the CUPID-0/Mo demonstrator, containing several kg of {sup 100}Mo. (orig.)

  13. Anisotrophic currents and flux jumps in high-Tc superconducting films with self-organized arrays of planar defects

    International Nuclear Information System (INIS)

    Yurchenko, V.V.; Qviller, A.J.; Mozhaev, P.B.; Mozhaeva, J.E.; Hansen, J.B.; Jacobsen, C.S.; Kotelyanskii, I.M.; Pan, A.V.; Johansen, T.H.

    2010-01-01

    Regular arrays of planar defects with a period of a few nanometers can be introduced in superconducting YBa 2 Cu 3 O 7-δ (YBCO) thin films by depositing them on vicinal (also called miscut or tilted) substrates. This results in the anisotropy of critical currents flowing in the plane of the film. We present results of real-time magneto-optical imaging (MOI) of magnetic flux distribution and dynamics in a series of YBCO thin films deposited on NdGaO 3 substrates with different miscut angles θ. MOI allows reconstructing the current flow profiles. From the angle formed between domains with different directions of the current flow we determine the anisotropy parameter of the in-plane current, as well as its field and temperature dependences. The artificially introduced defects also have a dramatic effect on the dynamics of the flux propagation: for 10 o o the magnetic flux propagates along the easy channels intermittently, i.e. in a form of flux jumps. This behavior is indicative of thermo-magnetic instability in superconductors, but we argue that this effect can be of a different nature.

  14. Magnetic tunable confinement of the superconducting condensate in superconductor/ferromagnet hybrids

    International Nuclear Information System (INIS)

    Aladyshkin, A.Yu.; Gillijns, W.; Silhanek, A.V.; Moshchalkov, V.V.

    2008-01-01

    The effect of a nonuniform magnetic field induced by a ferromagnet on the magnetoresistance of thin-film superconductor/ferromagnet hybrid structures was investigated experimentally. Two different magnetic textures with out-of-plane magnetization were considered: a plain ferromagnetic film with bubble domains and a regular array of ferromagnetic dots. The stray fields of the structures are able to affect the spatial profile of the superconducting condensate, leading to a modification of the dependence of the critical temperature T c on an external magnetic field H. We showed how the standard linear T c (H) dependence with a single maximum at H=0 can be continuously transformed into so-called reentrant phase boundary with two T c peaks. We demonstrated that both domain-wall superconductivity and field-induced superconductivity are different manifestations of the magnetic confinement effect in various magnetic patterns

  15. Superconductivity

    International Nuclear Information System (INIS)

    Taylor, A.W.B.; Noakes, G.R.

    1981-01-01

    This book is an elementray introduction into superconductivity. The topics are the superconducting state, the magnetic properties of superconductors, type I superconductors, type II superconductors and a chapter on the superconductivity theory. (WL)

  16. Superconductivity

    International Nuclear Information System (INIS)

    Onnes, H.K.

    1988-01-01

    The author traces the development of superconductivity from 1911 to 1986. Some of the areas he explores are the Meissner Effect, theoretical developments, experimental developments, engineering achievements, research in superconducting magnets, and research in superconducting electronics. The article also mentions applications shown to be technically feasible, but not yet commercialized. High-temperature superconductivity may provide enough leverage to bring these applications to the marketplace

  17. Construction and test of a superconducting phase-transition thermometer for bolometric cryodetectors

    International Nuclear Information System (INIS)

    Meier, H.J.

    1990-10-01

    In the framework of a project for the study of bolometric cryodetectors for the detection of heavy ions a superconducting phase-transition thermometer for the detection of heavy ions was constructed and tested with α particles. The thermometer consists of a 10 nm thick aluminium film, which was evaporated on a sapphire absorber with a typical magnitude of 2.5x2.5 x 0.33 mm 3 . By the method of photolithography the aluminium film was structured in form of a meander. By this at the working point of the thermometer resistances of up to 60 kΩ resulted, so that the signal acquisition was possible with usual readout electronics. Several of these thermometers were constructed, characterized in their properties, and tested. For the study of the detector properties of the thermometers in characterization measurements the width of the phase transitions dT ≅ 2 mK, the temperature dependence of the resistance to dR/dT ≅ 10MΩ/K, the thermal conductivity of the thermal coupling to the cooling bath, and the heat capacity of the bolometers to C ≅ 2 nJ/K were determined.The best energy resolution, which was reached with one of the superconducting phase-transition thermometers, amounts to 50 keV for 5.5 MeV α particles, which corresponds to a relative resolution of 0,9%. By this in the order of magnitude the quality of semiconductor detectors was reached. The best temperature resolution amounts to about 1 μK. (orig./HSI) [de

  18. Superconductivity

    International Nuclear Information System (INIS)

    Andersen, N.H.; Mortensen, K.

    1988-12-01

    This report contains lecture notes of the basic lectures presented at the 1st Topsoee Summer School on Superconductivity held at Risoe National Laboratory, June 20-24, 1988. The following lecture notes are included: L.M. Falicov: 'Superconductivity: Phenomenology', A. Bohr and O. Ulfbeck: 'Quantal structure of superconductivity. Gauge angle', G. Aeppli: 'Muons, neutrons and superconductivity', N.F. Pedersen: 'The Josephson junction', C. Michel: 'Physicochemistry of high-T c superconductors', C. Laverick and J.K. Hulm: 'Manufacturing and application of superconducting wires', J. Clarke: 'SQUID concepts and systems'. (orig.) With 10 tabs., 128 figs., 219 refs

  19. Phase fluctuations in two coaxial quasi-one-dimensional superconducting cylindrical surfaces serving as a model system for superconducting nanowire bundles

    Energy Technology Data Exchange (ETDEWEB)

    Wong, C.H., E-mail: ch.kh.vong@urfu.ru [Institute of Physics and Technology, Ural Federal University, Clear Water Bay, Kowloon (Russian Federation); Wu, R.P.H., E-mail: pak-hong-raymond.wu@connect.polyu.hk [Department of Applied Physics, The Hong Kong Polytechnic University (Hong Kong); Lortz, R., E-mail: lortz@ust.hk [Department of Physics, Hong Kong University of Science and Technology (Hong Kong)

    2017-03-15

    The dimensional crossover from a 1D fluctuating state at high temperatures to a 3D phase coherent state in the low temperature regime in two coaxial weakly-coupled cylindrical surfaces formed by two-dimensional arrays of parallel nanowires is studied via an 8-state 3D-XY model. This system serves as a model for quasi-one-dimensional superconductors in the form of bundles of weakly-coupled superconducting nanowires. A periodic variation of the dimensional crossover temperature T{sub DC} is observed when the inner superconducting cylindrical surface is rotated in the angular plane. T{sub DC} reaches a maximum when the relative angle between the cylinders is 2.81°, which corresponds to the maximum separation of nanowires between the two cylindrical surfaces. We demonstrate that the relative strength of phase fluctuations in this system is controllable by the rotational angle between the two surfaces with a strong suppression of the fluctuation strength at 2.81°. The phase fluctuations are suppressed gradually upon cooling, before they abruptly vanish below T{sub DC}. Our model thus allows us to study how phase fluctuations can be suppressed in quasi-one-dimensional superconductors in order to achieve a global phase coherent state throughout the nanowire array with zero electric resistance.

  20. Higgsless superconductivity from topological defects in compact BF terms

    Directory of Open Access Journals (Sweden)

    M. Cristina Diamantini

    2015-02-01

    Full Text Available We present a new Higgsless model of superconductivity, inspired from anyon superconductivity but P- and T-invariant and generalisable to any dimension. While the original anyon superconductivity mechanism was based on incompressible quantum Hall fluids as average field states, our mechanism involves topological insulators as average field states. In D space dimensions it involves a (D−1-form fictitious pseudovector gauge field which originates from the condensation of topological defects in compact low-energy effective BF theories. In the average field approximation, the corresponding uniform emergent charge creates a gap for the (D−2-dimensional branes via the Magnus force, the dual of the Lorentz force. One particular combination of intrinsic and emergent charge fluctuations that leaves the total charge distribution invariant constitutes an isolated gapless mode leading to superfluidity. The remaining massive modes organise themselves into a D-dimensional charged, massive vector. There is no massive Higgs scalar as there is no local order parameter. When electromagnetism is switched on, the photon acquires mass by the topological BF mechanism. Although the charge of the gapless mode (2 and the topological order (4 are the same as those of the standard Higgs model, the two models of superconductivity are clearly different since the origins of the gap, reflected in the high-energy sectors are totally different. In 2D this type of superconductivity is explicitly realised as global superconductivity in Josephson junction arrays. In 3D this model predicts a possible phase transition from topological insulators to Higgsless superconductors.

  1. Development of a superconducting transition edge thermometer for calorimetric detection of heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Meier, J; Boehmer, W; Egelhof, P; Henning, W; Kienlin, A v [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany) Mainz Univ. (Germany). Inst. fuer Physik; Shepard, K W [Argonne National Lab., IL (United States)

    1991-10-01

    A low temperature bolometer for the calorimetric detection of heavy ions was constructed and tested. An aluminium thin-film microstrip, patterned in a meander-line structure by photolithographic techniques, serves as superconducting transition edge thermometer on a sapphire absorber. A transition width {delta}T of the thermometer of the order of some mK, and a resistance of up to R{sub c} = 60 k{Omega} at the working point (T{sub c} {approx equal} 1.5 K) is achieved. In tests with {alpha}-particles signals of typically 1 V pulseheight after the preamplifier and decaytimes around hundred {mu}s were observed. For 5.5 MeV {alpha}-particles the measured energy resolution is {Delta}E = 50 keV, corresponding to a temperature resolution of about 1 {mu}K. First measurements were performed with {sup 20}Ne ions (E = 116 MeV). The dependence of the pulseheight and the FWHM on the working point were investigated and qualitatively explained. The best energy resolution was {Delta}E = 2.6 MeV; most probably the present limitations are determined by the temperature stabilization. (orig.).

  2. Theory of superconductivity

    International Nuclear Information System (INIS)

    Crisan, M.

    1988-01-01

    This book discusses the most important aspects of the theory. The phenomenological model is followed by the microscopic theory of superconductivity, in which modern formalism of the many-body theory is used to treat most important problems such as superconducting alloys, coexistence of superconductivity with the magnetic order, and superconductivity in quasi-one-dimensional systems. It concludes with a discussion on models for exotic and high temperature superconductivity. Its main aim is to review, as complete as possible, the theory of superconductivity from classical models and methods up to the 1987 results on high temperature superconductivity. Contents: Phenomenological Theory of Superconductivity; Microscopic Theory of Superconductivity; Theory of Superconducting Alloys; Superconductors in a Magnetic Field; Superconductivity and Magnetic Order; Superconductivity in Quasi-One-Dimensional Systems; and Non-Conventional Superconductivity

  3. Applied superconductivity

    CERN Document Server

    Newhouse, Vernon L

    1975-01-01

    Applied Superconductivity, Volume II, is part of a two-volume series on applied superconductivity. The first volume dealt with electronic applications and radiation detection, and contains a chapter on liquid helium refrigeration. The present volume discusses magnets, electromechanical applications, accelerators, and microwave and rf devices. The book opens with a chapter on high-field superconducting magnets, covering applications and magnet design. Subsequent chapters discuss superconductive machinery such as superconductive bearings and motors; rf superconducting devices; and future prospec

  4. Fabrication of Detector Arrays for the SPT-3G Receiver

    Science.gov (United States)

    Posada, C. M.; Ade, P. A. R.; Ahmed, Z.; Anderson, A. J.; Austermann, J. E.; Avva, J. S.; Thakur, R. Basu; Bender, A. N.; Benson, B. A.; Carlstrom, J. E.; Carter, F. W.; Cecil, T.; Chang, C. L.; Cliche, J. F.; Cukierman, A.; Denison, E. V.; de Haan, T.; Ding, J.; Divan, R.; Dobbs, M. A.; Dutcher, D.; Everett, W.; Foster, A.; Gannon, R. N.; Gilbert, A.; Groh, J. C.; Halverson, N. W.; Harke-Hosemann, A. H.; Harrington, N. L.; Henning, J. W.; Hilton, G. C.; Holzapfel, W. L.; Huang, N.; Irwin, K. D.; Jeong, O. B.; Jonas, M.; Khaire, T.; Kofman, A. M.; Korman, M.; Kubik, D.; Kuhlmann, S.; Kuo, C. L.; Lee, A. T.; Lowitz, A. E.; Meyer, S. S.; Michalik, D.; Miller, C. S.; Montgomery, J.; Nadolski, A.; Natoli, T.; Nguyen, H.; Noble, G. I.; Novosad, V.; Padin, S.; Pan, Z.; Pearson, J.; Rahlin, A.; Ruhl, J. E.; Saunders, L. J.; Sayre, J. T.; Shirley, I.; Shirokoff, E.; Smecher, G.; Sobrin, J. A.; Stan, L.; Stark, A. A.; Story, K. T.; Suzuki, A.; Tang, Q. Y.; Thompson, K. L.; Tucker, C.; Vale, L. R.; Vanderlinde, K.; Vieira, J. D.; Wang, G.; Whitehorn, N.; Yefremenko, V.; Yoon, K. W.; Young, M. R.

    2018-05-01

    The South Pole Telescope third-generation (SPT-3G) receiver was installed during the austral summer of 2016-2017. It is designed to measure the cosmic microwave background across three frequency bands centered at 95, 150, and 220 GHz. The SPT-3G receiver has ten focal plane modules, each with 269 pixels. Each pixel features a broadband sinuous antenna coupled to a niobium microstrip transmission line. In-line filters define the desired band-passes before the signal is coupled to six bolometers with Ti/Au/Ti/Au transition edge sensors (three bands × two polarizations). In total, the SPT-3G receiver is composed of 16,000 detectors, which are read out using a 68× frequency-domain multiplexing scheme. In this paper, we present the process employed in fabricating the detector arrays.

  5. Avalanche effect in the planar array of superheated superconductors

    International Nuclear Information System (INIS)

    Meagher, G.; Pond, J.; Kotlicki, A.; Turrell, B.G.; Eska, G.; Drukier, A.K.

    1996-01-01

    An avalanche effect has been observed in a cryogenic detector based on the planar array of superheated superconductors (PASS). The indium PASS, fabricated by photolithography on a mylar substrate, consisted of 40 well-separated lines each containing about 175 spheres of diameter 18 μm and separation 20 μm with those at the end being shielded by superconducting wire. The magnetic field was applied in the PASS plane parallel to the lines. Avalanche events in which several granules changed their state from superconducting to normal were triggered by the nucleation of the transition in a single grain by an alpha particle. (author)

  6. Superconductivity

    International Nuclear Information System (INIS)

    Caruana, C.M.

    1988-01-01

    Despite reports of new, high-temperature superconductive materials almost every day, participants at the First Congress on Superconductivity do not anticipate commercial applications with these materials soon. What many do envision is the discovery of superconducting materials that can function at much warmer, perhaps even room temperatures. Others hope superconductivity will usher in a new age of technology as semiconductors and transistors did. This article reviews what the speakers had to say at the four-day congress held in Houston last February. Several speakers voiced concern that the Reagan administration's apparent lack of interest in funding superconductivity research while other countries, notably Japan, continue to pour money into research and development could hamper America's international competitiveness

  7. Superconducting NbN detectors for synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Semenov, Alexei; Richter, Heiko; Huebers, Heinz-Wilhelm [DLR, Instiute of Planetary Research, Berlin (Germany); Ilin, Konstantin; Siegel, Michael [Institute of Micro- and Nanoelectronic Systems, University of Karlsruhe (Germany)

    2009-07-01

    We present development of a special type of hot-electron bolometers that is designed to optimally detect pulsed synchrotron radiation in the terahertz frequency range. The enlarged log-spiral antenna makes it possible to sense the low-frequency part of the spectrum in coherent and non-coherent regime. The device follows the layout of a typical HEB mixer. The radiation is coupled quasioptically with the 6-mm elliptical silicon lens. The bolometer has the noise equivalent power 2 nW per square root Hz and responds to a few picoseconds long radiation pulse with the electric pulse having full width at half maximum of 160 ps. We present results obtained with this type of detector at different synchrotron facilities and discuss possible improvements of the detector performance.

  8. Development of a superconducting elliptically polarized undulator

    International Nuclear Information System (INIS)

    Chen, S D; Liang, K S; Jan, J C; Hwang, C S

    2010-01-01

    A superconducting, elliptically polarized undulator (SEPU24) with a period of length 24 mm was developed to provide first-harmonic photons from a 0.8 GeV storage ring for extreme-ultraviolet (EUV) lithography experiment. In SEPU24, two layers of a magnet array structure - with and without rotated magnet arrays - are combined to generate a helical field that provides radiation with wavelength 13.5 nm in the in-band energy. The arrays of iron and aluminium poles were wound with a racetrack coil vertically as for the magnet pole array. The elliptical field is created when the up and down magnet-pole arrays pass excitation currents in alternate directions. SEPU24 is designed with a magnet of gap 6.8 mm, yielding magnetic flux density B x =B z =0.61 T of the helical field. A prototype magnet was fabricated with a diode for quench protection, and assembled in a test dewar to test the magnet performance. A cryogenic Hall-probe system with a precise linear stage was used to measure the distribution of the magnetic field. We describe the design concept and algorithm, the engineering design, the calculation of the magnetic field, the construction and testing of the 10-pole prototype magnet and related issues.

  9. Diagnosing x-ray power and energy of tungsten wire array z-pinch with a flat spectral response x-ray diode

    International Nuclear Information System (INIS)

    Wang, Kun-lun; Ren, Xiao-dong; Huang, Xian-bin; Zhang, Si-qun; Zhou, Shao-tong; Dan, Jia-kun; Li, Jing; Xu, Qiang; Ouyang, Kai; Cai, Hong-chun; Wei, Bing; Ji, Ce; Feng, Shu-ping; Wang, Meng; Xie, Wei-ping; Deng, Jian-jun

    2015-01-01

    Fast z-pinch is a very efficient way of converting electromagnetic energy to radiation. With an 8-10 MA current on primary test stand facility, about 1 MJ electromagnetic energy is delivered to vacuum chamber, which heats z-pinch plasma to radiate soft x-ray. To develop a pulsed high power x-ray source, we studied the applicability of diagnosing x-ray power from tungsten wire array z-pinch with a flat spectral response x-ray diode (FSR-XRD). The detector was originally developed to diagnose radiation of a hohlraum in SG-III prototype laser facility. It utilized a gold cathode XRD and a specially configured compound gold filter to yield a nearly flat spectral response in photon energy range of 0.1-4 keV. In practice, it was critical to avoid surface contamination of gold cathode. It is illustrated that an exposure of an XRD to multiple shots caused a significant change of response. Thus, in diagnosing x-ray power and energy, we used each XRD in only one shot after calibration. In a shot serial, output of FSR-XRD was compared with output of a nickel bolometer. In these shots, the outputs agreed with each other within their uncertainties which were about 12% for FSR-XRD and about 15% for bolometer. Moreover, the ratios between the FSR-XRD and the bolometer among different shots were explored. In 8 shots, the standard deviation of the ratio was 6%. It is comparable to XRD response change of 7%

  10. Instrumentation for localized superconducting cavity diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Conway, Z. A. [Argonne National Lab. (ANL), Argonne, IL (United States). Physics Division; Ge, M. [Cornell Lab. for Accelerator-Based Sciences and Education, Ithaca, NY (United States); Iwashita, Y. [Kyoto Univ. (Japan)

    2017-01-12

    Superconducting accelerator cavities are now routinely operated at levels approaching the theoretical limit of niobium. To achieve these operating levels more information than is available from the RF excitation signal is required to characterize and determine fixes for the sources of performance limitations. This information is obtained using diagnostic techniques which complement the analysis of the RF signal. In this paper we describe the operation and select results from three of these diagnostic techniques: the use of large scale thermometer arrays, second sound wave defect location and high precision cavity imaging with the Kyoto camera.

  11. Performance of an on-chip superconducting circulator for quantum microwave systems

    Science.gov (United States)

    Chapman, Benjamin; Rosenthal, Eric; Moores, Bradley; Kerckhoff, Joseph; Mates, J. A. B.; Hilton, G. C.; Vale, L. R.; Ullom, J. N.; LalumíEre, Kevin; Blais, Alexandre; Lehnert, K. W.

    Microwave circulators enforce a single propagation direction for signals in an electrical network. Unfortunately, commercial circulators are bulky, lossy, and cannot be integrated close to superconducting circuits because they require strong ( kOe) magnetic fields produced by permanent magnets. Here we report on the performance of an on-chip, active circulator for superconducting microwave circuits, which uses no permanent magnets. Non-reciprocity is achieved by actively modulating reactive elements around 100 MHz, giving roughly a factor of 50 in the separation between signal and control frequencies, which facilitates filtering. The circulator's active components are dynamically tunable inductors constructed with arrays of dc-SQUIDs in series. Array inductance is tuned by varying the magnetic flux through the SQUIDs with fields weaker than 1 Oe. Although the instantaneous bandwidth of the device is narrow, the operation frequency is tunable between 4 and 8 GHz. This presentation will describe the device's theory of operation and compare its measured performance to design goals. This work is supported by the ARO under contract W911NF-14-1-0079 and the National Science Foundation under Grant Number 1125844.

  12. Fabrication of High-T(sub c) Hot-Electron Bolometric Mixers for Terahertz Applications

    Science.gov (United States)

    Burns, M. J.; Kleinsasser, A. W.; Delin, K. A.; Vasquez, R. P.; Karasik, B. S.; McGrath, W. R.; Gaidis, M. C.

    1996-01-01

    Superocnducting hot-electron bolometers (HEB) represent a promising candidate for heterodyne mixing at frequencies exceeding 1 THz. Nb HEB mixers offer performance competitive with tunnel junctions without the frequency limit imposed by the superconducting energy gap.

  13. Advanced ACTPol Multichroic Polarimeter Array Fabrication Process for 150 mm Wafers

    Science.gov (United States)

    Duff, S. M.; Austermann, J.; Beall, J. A.; Becker, D.; Datta, R.; Gallardo, P. A.; Henderson, S. W.; Hilton, G. C.; Ho, S. P.; Hubmayr, J.; Koopman, B. J.; Li, D.; McMahon, J.; Nati, F.; Niemack, M. D.; Pappas, C. G.; Salatino, M.; Schmitt, B. L.; Simon, S. M.; Staggs, S. T.; Stevens, J. R.; Van Lanen, J.; Vavagiakis, E. M.; Ward, J. T.; Wollack, E. J.

    2016-08-01

    Advanced ACTPol (AdvACT) is a third-generation cosmic microwave background receiver to be deployed in 2016 on the Atacama Cosmology Telescope (ACT). Spanning five frequency bands from 25 to 280 GHz and having just over 5600 transition-edge sensor (TES) bolometers, this receiver will exhibit increased sensitivity and mapping speed compared to previously fielded ACT instruments. This paper presents the fabrication processes developed by NIST to scale to large arrays of feedhorn-coupled multichroic AlMn-based TES polarimeters on 150-mm diameter wafers. In addition to describing the streamlined fabrication process which enables high yields of densely packed detectors across larger wafers, we report the details of process improvements for sensor (AlMn) and insulator (SiN_x) materials and microwave structures, and the resulting performance improvements.

  14. A rad-hard, steady state, digital imaging bolometer system for ITER

    International Nuclear Information System (INIS)

    Wurden, G.A.

    1995-01-01

    The concept and design of a new type of bolometer system which can function with excellent spatial resolution and good time resolution in the next generation of long-pulse (or steady-state), harsh-neutron environment fusion plasmas, is outlined. It uses a cooled pinhole camera design, employing a robust, passive, segmented radiation absorber, cooled from the back-side. Infrared emission from the absorber's front surface is relayed by metal mirror optics to a shielded, high-resolution IR video camera with ± 0.01 C temperature resolution. It can make thousands of simultaneous ''pixel'' measurements at up to 50--60 Hz, without any signal wires through the vacuum interface

  15. Design of a 16 kbit superconducting latching/SFQ hybrid RAM

    International Nuclear Information System (INIS)

    Nagasawa, Shuichi; Hasegawa, Haruhiro; Hashimoto, Tatsunori; Suzuki, Hideo; Miyahara, Kazunori; Enomoto, Youichi

    1999-01-01

    We have designed a 16 kbit superconducting latching/SFQ hybrid (SLASH) RAM, which enables high-frequency clock operation up to 10 GHz. The 16 kbit SLASH RAM consists of four 4x4 matrix arrays of 256 bit RAM blocks, block decoders, latching block drivers, latching block senses, impedance matched lines and the powering circuits. The 256 bit RAM block is composed of a 16x16 matrix array of vortex transitional memory cells, latching drivers, SFQ NOR decoders and latching sense circuits. We have also designed and implemented an SFQ NOR decoder that is composed of magnetically coupled multi-input OR gates and RSFQ inverters. (author)

  16. Measurement of the energy and power radiated by a pulsed blackbody x-ray source

    International Nuclear Information System (INIS)

    Chandler, Gordon Andrew; McDaniel, Dillon Heirman; Jorgenson, Roy E.; Warne, Larry Kevin; Dropinski, Steven Clark; Hanson, Donald L.; Johnson, William Arthur; York, Mathew William; Lewis, D.F.; Korde, R.; Haslett, C.L.; Wall, D.L.; Ruggles, Laurence E.; Ramirez, L.E.; Stygar, William A.; Porter, John Larry Jr.; McKenney, John Lee; Bryce, Edwin Anthony; Cuneo, Michael Edward; Torres, Jose A.; Mills, Jerry Alan; Leeper, Ramon Joe; McGurn, John Stephen; Fehl, David Lee; Spielman, R. B.; Pyle, John H.; Mazarakis, Michael Gerrassimos; Ives III, Harry Crockett; Seamen, Johann F.; Simpson, Walter W.

    2006-01-01

    We have developed a diagnostic system that measures the spectrally integrated (i.e. the total) energy and power radiated by a pulsed blackbody x-ray source. The total-energy-and-power (TEP) diagnostic system is optimized for blackbody temperatures between 50 and 350 eV. The system can view apertured sources that radiate energies and powers as high as 2 MJ and 200 TW, respectively, and has been successfully tested at 0.84 MJ and 73 TW on the Z pulsed-power accelerator. The TEP system consists of two pinhole arrays, two silicon-diode detectors, and two thin-film nickel bolometers. Each of the two pinhole arrays is paired with a single silicon diode. Each array consists of a 38 x 38 square array of 10-(micro)m-diameter pinholes in a 50-(micro)m-thick tantalum plate. The arrays achromatically attenuate the x-ray flux by a factor of ∼1800. The use of such arrays for the attenuation of soft x rays was first proposed by Turner and co-workers [Rev. Sci. Instrum. 70, 656 (1999)RSINAK0034-674810.1063/1.1149385]. The attenuated flux from each array illuminates its associated diode; the diode's output current is recorded by a data-acquisition system with 0.6-ns time resolution. The arrays and diodes are located 19 and 24 m from the source, respectively. Because the diodes are designed to have an approximately flat spectral sensitivity, the output current from each diode is proportional to the x-ray power. The nickel bolometers are fielded at a slightly different angle from the array-diode combinations, and view (without pinhole attenuation) the same x-ray source. The bolometers measure the total x-ray energy radiated by the source and--on every shot--provide an in situ calibration of the array-diode combinations. Two array-diode pairs and two bolometers are fielded to reduce random uncertainties. An analytic model (which accounts for pinhole-diffraction effects) of the sensitivity of an array-diode combination is presented

  17. Active terahertz imaging with Ne indicator lamp detector arrays

    Science.gov (United States)

    Kopeika, N. S.; Abramovich, A.; Yadid-Pecht, O.; Yitzhaky, Y.

    2009-08-01

    The advantages of terahertz (THz) imaging are well known. They penetrate well most non-conducting media and there are no known biological hazards, This makes such imaging systems important for homeland security, as they can be used to image concealed objects and often into rooms or buildings from the outside. There are also biomedical applications that are arising. Unfortunately, THz imaging is quite expensive, especially for real time systems, largely because of the price of the detector. Bolometers and pyroelectric detectors can each easily cost at least hundreds of dollars if not more, thus making focal plane arrays of them quite expensive. We have found that common miniature commercial neon indicator lamps costing typically about 30 cents each exhibit high sensitivity to THz radiation [1-3], with microsecond order rise times, thus making them excellent candidates for such focal plane arrays. NEP is on the order of 10-10 W/Hz1/2. Significant improvement of detection performance is expected when heterodyne detection is used Efforts are being made to develop focal plane array imagers using such devices at 300 GHz. Indeed, preliminary images using 4x4 arrays have already been obtained. An 8x8 VLSI board has been developed and is presently being tested. Since no similar imaging systems have been developed previously, there are many new problems to be solved with such a novel and unconventional imaging system. These devices act as square law detectors, with detected signal proportional to THz power. This allows them to act as mixers in heterodyne detection, thus allowing NEP to be reduced further by almost two orders of magnitude. Plans are to expand the arrays to larger sizes, and to employ super resolution techniques to improve image quality beyond that ordinarily obtainable at THz frequencies.

  18. Real-time data acquisition and parallel data processing solution for TJ-II Bolometer arrays diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Barrera, E. [Departamento de Sistemas Electronicos y de Control, Universidad Politecnica de Madrid, Crta. Valencia Km. 7, 28031 Madrid (Spain)]. E-mail: eduardo.barrera@upm.es; Ruiz, M. [Grupo de Investigacion en Instrumentacion y Acustica Aplicada, Universidad Politecnica de Madrid, Crta. Valencia Km. 7, 28031 Madrid (Spain); Lopez, S. [Departamento de Sistemas Electronicos y de Control, Universidad Politecnica de Madrid, Crta. Valencia Km. 7, 28031 Madrid (Spain); Machon, D. [Departamento de Sistemas Electronicos y de Control, Universidad Politecnica de Madrid, Crta. Valencia Km. 7, 28031 Madrid (Spain); Vega, J. [Asociacion EURATOM/CIEMAT para Fusion, 28040 Madrid (Spain); Ochando, M. [Asociacion EURATOM/CIEMAT para Fusion, 28040 Madrid (Spain)

    2006-07-15

    Maps of local plasma emissivity of TJ-II plasmas are determined using three-array cameras of silicon photodiodes (AXUV type from IRD). They have assigned the top and side ports of the same sector of the vacuum vessel. Each array consists of 20 unfiltered detectors. The signals from each of these detectors are the inputs to an iterative algorithm of tomographic reconstruction. Currently, these signals are acquired by a PXI standard system at approximately 50 kS/s, with 12 bits of resolution and are stored for off-line processing. A 0.5 s discharge generates 3 Mbytes of raw data. The algorithm's load exceeds the CPU capacity of the PXI system's controller in a continuous mode, making unfeasible to process the samples in parallel with their acquisition in a PXI standard system. A new architecture model has been developed, making possible to add one or several processing cards to a standard PXI system. With this model, it is possible to define how to distribute, in real-time, the data from all acquired signals in the system among the processing cards and the PXI controller. This way, by distributing the data processing among the system controller and two processing cards, the data processing can be done in parallel with the acquisition. Hence, this system configuration would be able to measure even in long pulse devices.

  19. Design and Expected Performance of GISMO-2, a Two Color Millimeter Camera for the IRAM 30 m Telescope

    Science.gov (United States)

    Staguhn, Johannes G.; Benford, Dominic J.; Dwek, Eli; Hilton, Gene; Fixsen, Dale J.; Irwin, Kent; Jhabvala, Christine; Kovacs, Attila; Leclercq, Samuel; Maher, Stephen F.; hide

    2014-01-01

    We present the main design features for the GISMO-2 bolometer camera, which we build for background-limited operation at the IRAM 30 m telescope on Pico Veleta, Spain. GISMO-2 will operate simultaneously in the 1 and 2 mm atmospherical windows. The 1 mm channel uses a 32 × 40 TES-based backshort under grid (BUG) bolometer array, the 2 mm channel operates with a 16 × 16 BUG array. The camera utilizes almost the entire full field of view provided by the telescope. The optical design of GISMO-2 was strongly influenced by our experience with the GISMO 2mm bolometer camera, which is successfully operating at the 30 m telescope. GISMO is accessible to the astronomical community through the regularIRAMcall for proposals.

  20. Conceptual design of Dump resistor for Superconducting CS of SST-1

    Science.gov (United States)

    Roy, Swati; Raj, Piyush; Panchal, Arun; Pradhan, Subrata

    2017-04-01

    Under upgradation activities for SST-1, the existing resistive central solenoid (CS) coil will be replaced with Nb3Sn based superconducting coil. Design of Central solenoid had been completed and some of the initiative has already taken for its manufacturing. The superconducting CS will store upto 3 MJ of magnetic energy per operation cycle with operating current upto 14 kA. During quench, energy stored in the coils has to be extracted rapidly with a time constant of 1.5 s by inserting a 20 mΩ dump resistor in series with the superconducting CS which is normally shorted by circuit breakers. As a critical part of the superconducting CS quench protection system, a conceptual design of the 20 mΩ dump resistor has been proposed. The required design aspects and a dimensional layout of the dump resistor for the new superconducting CS has been presented and discussed. The basic structure of the proposed dump resistor comprises of stainless steel grids connected in series in the form of meander to minimize the stray inductance and increase the surface area for cooling. Such an array of grids connected in series and parallel will cater to the electrical as well as thermal parameters. It will be cooled by natural convection. During operation, the estimated maximum temperature of the proposed dump resistor will raise upto 600 K.

  1. Imaging of current distributions in superconducting thin film structures; Abbildung von Stromverteilungen in supraleitenden Duennfilmstrukturen

    Energy Technology Data Exchange (ETDEWEB)

    Doenitz, D.

    2006-10-31

    Local analysis plays an important role in many fields of scientific research. However, imaging methods are not very common in the investigation of superconductors. For more than 20 years, Low Temperature Scanning Electron Microscopy (LTSEM) has been successfully used at the University of Tuebingen for studying of condensed matter phenomena, especially of superconductivity. In this thesis LTSEM was used for imaging current distributions in different superconducting thin film structures: - Imaging of current distributions in Josephson junctions with ferromagnetic interlayer, also known as SIFS junctions, showed inhomogeneous current transport over the junctions which directly led to an improvement in the fabrication process. An investigation of improved samples showed a very homogeneous current distribution without any trace of magnetic domains. Either such domains were not present or too small for imaging with the LTSEM. - An investigation of Nb/YBCO zigzag Josephson junctions yielded important information on signal formation in the LTSEM both for Josephson junctions in the short and in the long limit. Using a reference junction our signal formation model could be verified, thus confirming earlier results on short zigzag junctions. These results, which could be reproduced in this work, support the theory of d-wave symmetry in the superconducting order parameter of YBCO. Furthermore, investigations of the quasiparticle tunneling in the zigzag junctions showed the existence of Andreev bound states, which is another indication of the d-wave symmetry in YBCO. - The LTSEM study of Hot Electron Bolometers (HEB) allowed the first successful imaging of a stable 'Hot Spot', a self-heating region in HEB structures. Moreover, the electron beam was used to induce an - otherwise unstable - hot spot. Both investigations yielded information on the homogeneity of the samples. - An entirely new method of imaging the current distribution in superconducting interference

  2. Optically activated high Tc superconducting microbolometer

    International Nuclear Information System (INIS)

    Yefremenko, V; Gordiyenko, E; Shustakova, G; Bader, S D; Karapetrov, G; Novosad, V

    2006-01-01

    A laser beam, precisely focused on the patterned superconducting structure, was used to nucleate a resistive area that is sensitive to external thermal effects. The electron beam lithography and wet chemical etching were applied as pattern transfer processes in epitaxial Y-Ba-Cu-O films. Two different sensor designs were tested: (i) 3 millimeters long and 40 micrometers wide stripe and (ii) 1.25 millimeters long, and 50 micron wide meander -like structure. It is shown experimentally that scanning the laser beam along the stripe leads to physical displacement of the sensitive area and, therefore may be used as a basis for imaging over a broad spectral range. For example, patterning the superconducting film into a meander structure is equivalent to a two-dimensional detector array. In additional to the simplicity of the detector fabrication sequence (one step mask transfer), a clear advantage of this approach is the simplicity of the read-out process: an image is formed by registering the signal with only two electrical terminals. The proposed approach can be extended for imaging over a wide spectral range

  3. Interface superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Gariglio, S., E-mail: stefano.gariglio@unige.ch [DQMP, Université de Genève, 24 Quai E.-Ansermet, CH-1211 Genève (Switzerland); Gabay, M. [Laboratoire de Physique des Solides, Bat 510, Université Paris-Sud 11, Centre d’Orsay, 91405 Orsay Cedex (France); Mannhart, J. [Max Planck Institute for Solid State Research, 70569 Stuttgart (Germany); Triscone, J.-M. [DQMP, Université de Genève, 24 Quai E.-Ansermet, CH-1211 Genève (Switzerland)

    2015-07-15

    Highlights: • We discuss interfacial superconductivity, a field boosted by the discovery of the superconducting interface between LaAlO. • This system allows the electric field control and the on/off switching of the superconducting state. • We compare superconductivity at the interface and in bulk doped SrTiO. • We discuss the role of the interfacially induced Rashba type spin–orbit. • We briefly discuss superconductivity in cuprates, in electrical double layer transistor field effect experiments. • Recent observations of a high T{sub c} in a monolayer of FeSe deposited on SrTiO{sub 3} are presented. - Abstract: Low dimensional superconducting systems have been the subject of numerous studies for many years. In this article, we focus our attention on interfacial superconductivity, a field that has been boosted by the discovery of superconductivity at the interface between the two band insulators LaAlO{sub 3} and SrTiO{sub 3}. We explore the properties of this amazing system that allows the electric field control and on/off switching of superconductivity. We discuss the similarities and differences between bulk doped SrTiO{sub 3} and the interface system and the possible role of the interfacially induced Rashba type spin–orbit. We also, more briefly, discuss interface superconductivity in cuprates, in electrical double layer transistor field effect experiments, and the recent observation of a high T{sub c} in a monolayer of FeSe deposited on SrTiO{sub 3}.

  4. Superconducting resonator used as a beam phase detector

    Directory of Open Access Journals (Sweden)

    S. I. Sharamentov

    2003-05-01

    Full Text Available Beam-bunch arrival time has been measured for the first time by operating superconducting cavities, normally part of the linac accelerator array, in a bunch-detecting mode. The very high Q of the superconducting cavities provides high sensitivity and allows for phase-detecting low-current beams. In detecting mode, the resonator is operated at a very low field level comparable to the field induced by the bunched beam. Because of this, the rf field in the cavity is a superposition of a “pure” (or reference rf and the beam-induced signal. A new method of circular phase rotation (CPR, allowing extraction of the beam phase information from the composite rf field was developed. Arrival time phase determination with CPR is better than 1° (at 48 MHz for a beam current of 100 nA. The electronics design is described and experimental data are presented.

  5. Superconducting coil and method of stress management in a superconducting coil

    Science.gov (United States)

    McIntyre, Peter M.; Shen, Weijun; Diaczenko, Nick; Gross, Dan A.

    1999-01-01

    A superconducting coil (12) having a plurality of superconducting layers (18) is provided. Each superconducting layer (18) may have at least one superconducting element (20) which produces an operational load. An outer support structure (24) may be disposed outwardly from the plurality of layers (18). A load transfer system (22) may be coupled between at least one of the superconducting elements (20) and the outer support structure (24). The load transfer system (22) may include a support matrix structure (30) operable to transfer the operational load from the superconducting element (20) directly to the outer support structure (24). A shear release layer (40) may be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a shear stress between the superconducting element (20) and the support matrix structure (30). A compliant layer (42) may also be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a compressive stress on the superconducting element (20).

  6. Superconductive crossbar system for communication applications

    International Nuclear Information System (INIS)

    Murdock, B.; Kwong, Y.K.; Gimlett, J.

    1994-01-01

    This paper reviews current efforts toward the integration of a high-speed crossbar switch for digital communication applications. This system is an intelligent switching matrix for 128 inputs and 128 outputs, each capable of 2 Gbs (10 9 bits per second). An array of Josephson junction integrated circuits are interconnected with the use of a superconductive multichip module maintained at 4.2 K. This module is connected to room-temperature electronics by means of flexible cables, each containing impedance-matched microstrip transmission lines. Room-temperature interface electronics will permit interconversion between standard level input/output signals and Josephson junction logic levels. (orig.)

  7. SiGe Integrated Circuit Developments for SQUID/TES Readout

    Science.gov (United States)

    Prêle, D.; Voisin, F.; Beillimaz, C.; Chen, S.; Piat, M.; Goldwurm, A.; Laurent, P.

    2018-03-01

    SiGe integrated circuits dedicated to the readout of superconducting bolometer arrays for astrophysics have been developed since more than 10 years at APC. Whether for Cosmic Microwave Background (CMB) observations with the QUBIC ground-based experiment (Aumont et al. in astro-ph.IM, 2016. arXiv:1609.04372) or for the Hot and Energetic Universe science theme with the X-IFU instrument on-board of the ATHENA space mission (Barret et al. in SPIE 9905, space telescopes & instrumentation 2016: UV to γ Ray, 2016. https://doi.org/10.1117/12.2232432), several kinds of Transition Edge Sensor (TES) (Irwin and Hilton, in ENSS (ed) Cryogenic particle detection, Springer, Berlin, 2005) arrays have been investigated. To readout such superconducting detector arrays, we use time or frequency domain multiplexers (TDM, FDM) (Prêle in JINST 10:C08015, 2016. https://doi.org/10.1088/1748-0221/10/08/C08015) with Superconducting QUantum Interference Devices (SQUID). In addition to the SQUID devices, low-noise biasing and amplification are needed. These last functions can be obtained by using BiCMOS SiGe technology in an Application Specific Integrated Circuit (ASIC). ASIC technology allows integration of highly optimised circuits specifically designed for a unique application. Moreover, we could reach very low-noise and wide band amplification using SiGe bipolar transistor either at room or cryogenic temperatures (Cressler in J Phys IV 04(C6):C6-101, 1994. https://doi.org/10.1051/jp4:1994616). This paper discusses the use of SiGe integrated circuits for SQUID/TES readout and gives an update of the last developments dedicated to the QUBIC telescope and to the X-IFU instrument. Both ASIC called SQmux128 and AwaXe are described showing the interest of such SiGe technology for SQUID multiplexer controls.

  8. High-resolution gamma-ray spectroscopy with a microwave-multiplexed transition-edge sensor array

    Energy Technology Data Exchange (ETDEWEB)

    Noroozian, Omid [National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); Center for Astrophysics and Space Astronomy, University of Colorado, Boulder, Colorado 80309 (United States); Mates, John A. B.; Bennett, Douglas A.; Brevik, Justus A.; Fowler, Joseph W.; Gao, Jiansong; Hilton, Gene C.; Horansky, Robert D.; Irwin, Kent D.; Schmidt, Daniel R.; Vale, Leila R.; Ullom, Joel N. [National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); Kang, Zhao [Department of Physics, University of Colorado, Boulder, Colorado 80309 (United States)

    2013-11-11

    We demonstrate very high resolution photon spectroscopy with a microwave-multiplexed two-pixel transition-edge sensor (TES) array. We measured a {sup 153}Gd photon source and achieved an energy resolution of 63 eV full-width-at-half-maximum at 97 keV and an equivalent readout system noise of 86 pA/√(Hz) at the TES. The readout circuit consists of superconducting microwave resonators coupled to radio-frequency superconducting-quantum-interference-devices and transduces changes in input current to changes in phase of a microwave signal. We use flux-ramp modulation to linearize the response and evade low-frequency noise. This demonstration establishes one path for the readout of cryogenic X-ray and gamma-ray sensor arrays with more than 10{sup 3} elements and spectral resolving powers R=λ/Δλ>10{sup 3}.

  9. Superconductivity

    International Nuclear Information System (INIS)

    Kakani, S.L.; Kakani, Shubhra

    2007-01-01

    The monograph provides readable introduction to the basics of superconductivity for beginners and experimentalists. For theorists, the monograph provides nice and brief description of the broad spectrum of experimental properties, theoretical concepts with all details, which theorists should learn, and provides a sound basis for students interested in studying superconducting theory at the microscopic level. Special chapter on the theory of high-temperature superconductivity in cuprates is devoted

  10. Anisotrophic currents and flux jumps in high-T{sub c} superconducting films with self-organized arrays of planar defects

    Energy Technology Data Exchange (ETDEWEB)

    Yurchenko, V.V., E-mail: vitaliy.yurchenko@fys.uio.n [Department of Physics, University of Oslo, P.B. 1048, Blindern, 0316 Oslo (Norway); Qviller, A.J. [Department of Physics, University of Oslo, P.B. 1048, Blindern, 0316 Oslo (Norway); Mozhaev, P.B.; Mozhaeva, J.E. [Department of Physics, Technical University of Denmark, Kgs. Lyngby DK-2800 (Denmark); Institute of Physics and Technology RAS, Moscow 117218 (Russian Federation); Hansen, J.B.; Jacobsen, C.S. [Department of Physics, Technical University of Denmark, Kgs. Lyngby DK-2800 (Denmark); Kotelyanskii, I.M. [Institute of Radio Engineering and Electronics RAS, Fryazino, 141190 Moscow District (Russian Federation); Pan, A.V. [Institute for Superconducting and Electronic Materials, University of Wollongong, Northfields Avenue, Wollongong 2522 (Australia); Johansen, T.H. [Department of Physics, University of Oslo, P.B. 1048, Blindern, 0316 Oslo (Norway)

    2010-10-01

    Regular arrays of planar defects with a period of a few nanometers can be introduced in superconducting YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}(YBCO) thin films by depositing them on vicinal (also called miscut or tilted) substrates. This results in the anisotropy of critical currents flowing in the plane of the film. We present results of real-time magneto-optical imaging (MOI) of magnetic flux distribution and dynamics in a series of YBCO thin films deposited on NdGaO{sub 3} substrates with different miscut angles {theta}. MOI allows reconstructing the current flow profiles. From the angle formed between domains with different directions of the current flow we determine the anisotropy parameter of the in-plane current, as well as its field and temperature dependences. The artificially introduced defects also have a dramatic effect on the dynamics of the flux propagation: for 10{sup o}<{theta}<14{sup o} the magnetic flux propagates along the easy channels intermittently, i.e. in a form of flux jumps. This behavior is indicative of thermo-magnetic instability in superconductors, but we argue that this effect can be of a different nature.

  11. Flux flow, pinning, and resistive behavior in superconducting networks

    International Nuclear Information System (INIS)

    Teitel, S.

    1991-10-01

    We have studied the behavior of fluctuation effects in superconducting systems using numerical simulations of XY and Coulomb gas models. Flux flow resistance in two dimensional Josephson junction arrays has been calculated, and related to correlations in vortex structure. Randomness has been introduced, and its effects on the superconducting transition, and vortex mobility, have been studied. We find that randomness destroys phase coherence, yet the randomness induced pinning reduces flux flow resistance at low temperatures. Vortex line fluctuations in high temperature superconductors have been studied using a three dimensional XY model. We have considered the melting of the vortex line lattice, and the entanglement and cutting of vortex lines in the vortex line liquid phase. Vortex line entangling and cutting appear to occur on the same length scales in the liquid phase. The vortex structure function has been calculated and from it, elastic properties of the vortex line liquid have been inferred. The two dimensional classical Coulomb gas, where charges map onto vortices in the superconducting system, has been simulated. The melting transitions of ordered charge (vortex) lattices have been studied, and we find evidence that these transitions do not have the critical behavior expected from standard symmetry analysis

  12. Superconducting materials for large scale applications

    International Nuclear Information System (INIS)

    Scanlan, Ronald M.; Malozemoff, Alexis P.; Larbalestier, David C.

    2004-01-01

    Significant improvements in the properties of superconducting materials have occurred recently. These improvements are being incorporated into the latest generation of wires, cables, and tapes that are being used in a broad range of prototype devices. These devices include new, high field accelerator and NMR magnets, magnets for fusion power experiments, motors, generators, and power transmission lines. These prototype magnets are joining a wide array of existing applications that utilize the unique capabilities of superconducting magnets:accelerators such as the Large Hadron Collider, fusion experiments such as ITER, 930 MHz NMR, and 4 Tesla MRI. In addition, promising new materials such as MgB2 have been discovered and are being studied in order to assess their potential for new applications. In this paper, we will review the key developments that are leading to these new applications for superconducting materials. In some cases, the key factor is improved understanding or development of materials with significantly improved properties. An example of the former is the development of Nb3Sn for use in high field magnets for accelerators. In other cases, the development is being driven by the application. The aggressive effort to develop HTS tapes is being driven primarily by the need for materials that can operate at temperatures of 50 K and higher. The implications of these two drivers for further developments will be discussed. Finally, we will discuss the areas where further improvements are needed in order for new applications to be realized

  13. Vortex pinning in superconductors laterally modulated by nanoscale self-assembled arrays

    DEFF Research Database (Denmark)

    Vanacken, J.; Vinckx, W.; Moshchalkov, V.V.

    2008-01-01

    Being the exponent of the so-called "bottom-up" approach, self-assembled structures are now-a-days attracting a lot of attention in the fields of science and technology. In this work, we show that nanoscale self-assembled arrays used as templates can provide periodic modulation in superconducting...

  14. Digital base-band rf control system for the superconducting Darmstadt electron linear accelerator

    Directory of Open Access Journals (Sweden)

    M. Konrad

    2012-05-01

    Full Text Available The accelerating field in superconducting cavities has to be stabilized in amplitude and phase by a radio-frequency (rf control system. Because of their high loaded quality factor superconducting cavities are very susceptible for microphonics. To meet the increased requirements with respect to accuracy, availability, and diagnostics, the previous analog rf control system of the superconducting Darmstadt electron linear accelerator S-DALINAC has been replaced by a digital rf control system. The new hardware consists of two components: An rf module that converts the signal from the cavity down to the base-band and a field-programmable gate array board including a soft CPU that carries out the signal processing steps of the control algorithm. Different algorithms are used for normal-conducting and superconducting cavities. To improve the availability of the control system, techniques for automatic firmware and software deployment have been implemented. Extensive diagnostic features provide the operator with additional information. The architecture of the rf control system as well as the functionality of its components will be presented along with measurements that characterize the performance of the system, yielding, e.g., an amplitude stabilization down to (ΔA/A_{rms}=7×10^{-5} and a phase stabilization of (Δϕ_{rms}=0.8° for superconducting cavities.

  15. Superconductivity

    International Nuclear Information System (INIS)

    Langone, J.

    1989-01-01

    This book explains the theoretical background of superconductivity. Includes discussion of electricity, material fabrication, maglev trains, the superconducting supercollider, and Japanese-US competition. The authors reports the latest discoveries

  16. ac superconducting articles

    International Nuclear Information System (INIS)

    Meyerhoff, R.W.

    1977-01-01

    A noval ac superconducting cable is described. It consists of a composite structure having a superconducting surface along with a high thermally conductive material wherein the superconducting surface has the desired physical properties, geometrical shape and surface finish produced by the steps of depositing a superconducting layer upon a substrate having a predetermined surface finish and shape which conforms to that of the desired superconducting article, depositing a supporting layer of material on the superconducting layer and removing the substrate, the surface of the superconductor being a replica of the substrate surface

  17. Status of LUMINEU program to search for neutrinoless double beta decay of {sup 100}Mo with cryogenic ZnMoO{sub 4} scintillating bolometers

    Energy Technology Data Exchange (ETDEWEB)

    Danevich, F. A., E-mail: danevich@kinr.kiev.ua; Boiko, R. S.; Chernyak, D. M.; Kobychev, V. V. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Bergé, L.; Chapellier, M.; Drillien, A.-A.; Dumoulin, L.; Humbert, V.; Marcillac, P. de; Marnieros, S.; Marrache-Kikuchi, C.; Olivieri, E.; Plantevin, O.; Tenconi, M. [Centre de Sciences Nucléaires et de Sciences de la Matière, CNRS/IN2P3, Université Paris-Sud, 91405 Orsay (France); Coron, N.; Redon, T.; Torres, L. [IAS, CNRS, Université Paris-Sud, 91405 Orsay (France); Devoyon, L.; Koskas, F. [CEA, Centre d’Etudes Saclay, Orphée, 91191 Gif-Sur-Yvette Cedex (France); and others

    2015-10-28

    The LUMTNEU program aims at performing a pilot experiment on 0ν2β decay of {sup 100}Mo using radiopure ZnMoO{sub 4} crystals enriched in {sup 100}Mo operated as cryogenic scintillating bolometers. Large volume ZnMoO{sub 4} crystal scintillators (∼ 0.3 kg) were developed and tested showing high performance in terms of radiopurity, energy resolution and α/β particle discrimination capability. Zinc molybdate crystal scintillators enriched in {sup 100}Mo were grown for the first time by the low-thermal-gradient Czochralski technique with a high crystal yield and an acceptable level of enriched molybdenum irrecoverable losses. A background level of ∼ 0.5 counts/(yr keV ton) in the region of interest can be reached in a large detector array thanks to the excellent detectors radiopurity and particle discrimination capability, suppression of randomly coinciding events by pulse-shape analysis, and anticoincidence cut. These results pave the way to future sensitive searches based on the LUMTNEU technology, capable of approachingand exploring the inverted hierarchy region of the neutrino mass pattern.

  18. High-temperature superconductivity

    International Nuclear Information System (INIS)

    Ginzburg, V.L.

    1987-07-01

    After a short account of the history of experimental studies on superconductivity, the microscopic theory of superconductivity, the calculation of the control temperature and its possible maximum value are presented. An explanation of the mechanism of superconductivity in recently discovered superconducting metal oxide ceramics and the perspectives for the realization of new high-temperature superconducting materials are discussed. 56 refs, 2 figs, 3 tabs

  19. Superconducting accelerator technology

    International Nuclear Information System (INIS)

    Grunder, H.A.; Hartline, B.K.

    1986-01-01

    Modern and future accelerators for high energy and nuclear physics rely increasingly on superconducting components to achieve the required magnetic fields and accelerating fields. This paper presents a practical overview of the phenomenon of superconductivity, and describes the design issues and solutions associated with superconducting magnets and superconducting rf acceleration structures. Further development and application of superconducting components promises increased accelerator performance at reduced electric power cost

  20. Improved signal to noise ratio and sensitivity of an infrared imaging video bolometer on large helical device by using an infrared periscope

    International Nuclear Information System (INIS)

    Pandya, Shwetang N.; Sano, Ryuichi; Peterson, Byron J.; Mukai, Kiyofumi; Enokuchi, Akito; Takeyama, Norihide

    2014-01-01

    An Infrared imaging Video Bolometer (IRVB) diagnostic is currently being used in the Large Helical Device (LHD) for studying the localization of radiation structures near the magnetic island and helical divertor X-points during plasma detachment and for 3D tomography. This research demands high signal to noise ratio (SNR) and sensitivity to improve the temporal resolution for studying the evolution of radiation structures during plasma detachment and a wide IRVB field of view (FoV) for tomography. Introduction of an infrared periscope allows achievement of a higher SNR and higher sensitivity, which in turn, permits a twofold improvement in the temporal resolution of the diagnostic. Higher SNR along with wide FoV is achieved simultaneously by reducing the separation of the IRVB detector (metal foil) from the bolometer's aperture and the LHD plasma. Altering the distances to meet the aforesaid requirements results in an increased separation between the foil and the IR camera. This leads to a degradation of the diagnostic performance in terms of its sensitivity by 1.5-fold. Using an infrared periscope to image the IRVB foil results in a 7.5-fold increase in the number of IR camera pixels imaging the foil. This improves the IRVB sensitivity which depends on the square root of the number of IR camera pixels being averaged per bolometer channel. Despite the slower f-number (f/# = 1.35) and reduced transmission (τ 0 = 89%, due to an increased number of lens elements) for the periscope, the diagnostic with an infrared periscope operational on LHD has improved in terms of sensitivity and SNR by a factor of 1.4 and 4.5, respectively, as compared to the original diagnostic without a periscope (i.e., IRVB foil being directly imaged by the IR camera through conventional optics). The bolometer's field of view has also increased by two times. The paper discusses these improvements in apt details

  1. An implanted $^{228}$Ra source for response characterization of bolometers

    CERN Multimedia

    TeO$_{2}$ crystals are used as bolometers in experiments searching for Double $\\beta$ Decay without emission of neutrinos. One of the most important issues in this extremely delicate kind of experiments is the discrimination of the background from the real signal. A deep knowledge of the bolometric response to $\\alpha$-particles is therefore needed to recognize and discard them, since it has been proven that $\\alpha$ surface contamination could be a major contribution in our background budget. We would like to use ISOLDE’s capability of implanting $^{228}$Ra to make a long-lived source feeding several monochromatic $\\alpha$- and recoiling nuclei, with little or no $\\alpha$-peak broadening due to the source itself, for tests of our detectors in Milano and Gran Sasso INFN National Lab.

  2. Magnetic properties of strip-like Josephson-junction arrays

    International Nuclear Information System (INIS)

    Chen, D.-X; Moreno, J.J.; Hernando, A.; Sanchez, A.

    2000-01-01

    Zero-field-cooled (ZFC) and field-cooled (FC) magnetic properties of strip-like Josephson-junction (JJ) arrays with very strong demagnetizing effects are calculated from basic laws. Similar to slab-like JJ arrays without considering demagnetizing effects, a vortex state evolves to a critical state (CS) with increasing maximum JJ currents in the ZFC case, and a vortex state always remains with a negative low-field susceptibility in the FC case. However, the strong demagnetizing effects cause qualitative changes in the CS, where the overall feature of the field and current profiles turns out to be similar to that in type-II superconducting strips, but not like the ordinary Bean CS in slab-like JJ arrays, the CS current profile is never flat and the critical current is no longer a step function of the maximum JJ current as in slab-like JJ arrays. The calculated results of different types of JJ arrays indicate that although the intergranular CS in granular superconductors may have a common origin, the discovered paramagnetic Meissner effect in them is still difficult to explain. (author)

  3. Superconducting technology

    International Nuclear Information System (INIS)

    2010-01-01

    Superconductivity has a long history of about 100 years. Over the past 50 years, progress in superconducting materials has been mainly in metallic superconductors, such as Nb, Nb-Ti and Nb 3 Sn, resulting in the creation of various application fields based on the superconducting technologies. High-T c superconductors, the first of which was discovered in 1986, have been changing the future vision of superconducting technology through the development of new application fields such as power cables. On basis of these trends, future prospects of superconductor technology up to 2040 are discussed. In this article from the viewpoints of material development and the applications of superconducting wires and electronic devices. (author)

  4. Study and optimization of bolometers designed to measure both ionization and heat in order to detect black matter

    International Nuclear Information System (INIS)

    Navick, X.F.

    1997-01-01

    The detection of black matter in the form of wimp (weakly interactive massive particle) requires the identification of the incident particle so that events due to wimp interactions can be set apart from events due to surrounding radioactivity. Bolometers allow to measure both the energy deposited and the ionization made by a particle. The amount of energy is determined by calorimetry. Wimp detection implies bolometers to run at very low temperature. After a presentation of particle interactions with matter, this thesis describes the physical phenomena involved in heat and ionization measurements. The behaviour of semiconductors at low temperature is investigated and qualitative expectations are drawn about the working of metal-semiconductor interface and the pin diode. An experimental setting is presented. The operating voltage needs to be very low in order to be the least disturbing possible. At so low voltage, a decrease of the ionization signal in terms of time appears. It is shown that this phenomenon is linked to the level density in the forbidden band of the semiconductor and to the intensity of infrared radiation reaching the detector. (A.C.)

  5. Conceptual design of dump resistor for superconducting CS of SST-1

    International Nuclear Information System (INIS)

    Roy, Swati; Pradhan, Subrata; Panchal, Arun

    2015-01-01

    During the upgradation of SST-1, the resistive central solenoid (CS) coil has been planned to be replaced with Nb 3 Sn based superconducting coil. The superconducting CS will store upto 3.5MJ of magnetic energy per operation cycle with operating current upto 14kA. In case of coil quench, the energy stored in the coils is to be extracted rapidly with a time constant of 1.5s. This will be achieved by inserting a 20m Ohm dump resistor in series with the superconducting CS which is normally shorted by circuit breakers. As a vital part of the superconducting CS quench protection system, a conceptual design of the 20m Ohm dump resistor has been proposed. In this paper, the required design aspects and a dimensional layout of the dump resistor for the new superconducting CS has been presented. Natural air circulation is proposed as cooling method for this dump resistor. The basic structure of the proposed dump resistor comprises of stainless steel grids connected in series in the shape of meander to minimize the stray inductance and increase the surface area for cooling. The entire dump resistor will be an array of such grids connected in series and parallel to meet electrical as well as thermal parameters. The maximum temperature of the proposed dump resistor is upto 350 °C during dump 3.5MJ energy. The proposed design permits indigenous fabrication of the dump resistor using commercially available welding techniques. (author)

  6. Identification of near surface events using athermal phonon signals in low temperature Ge bolometers for the EDELWEISS experiment

    International Nuclear Information System (INIS)

    Marnieros, S.; Juillard, A.; Berge, L.; Collin, S.; Dumoulin, L.

    2004-01-01

    We present a study of a 100 g low temperature Ge detector, allowing identification of surface events down to the energy threshold. The bolometer is fitted with segmented electrodes and two NbSi Anderson insulator thermometric layers. Analysis of the athermal signals amplitudes allows us to identify and reject all events occurring in the first millimeter under the electrodes

  7. Identification of near surface events using athermal phonon signals in low temperature Ge bolometers for the EDELWEISS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Marnieros, S. E-mail: marniero@csnsm.in2p3.fr; Juillard, A.; Berge, L.; Collin, S.; Dumoulin, L

    2004-03-11

    We present a study of a 100 g low temperature Ge detector, allowing identification of surface events down to the energy threshold. The bolometer is fitted with segmented electrodes and two NbSi Anderson insulator thermometric layers. Analysis of the athermal signals amplitudes allows us to identify and reject all events occurring in the first millimeter under the electrodes.

  8. X-Ray Calorimeter Arrays for Astrophysics

    Science.gov (United States)

    Kilbourne, Caroline A.

    2009-01-01

    High-resolution x-ray spectroscopy is a powerful tool for studying the evolving universe. The grating spectrometers on the XMM and Chandra satellites started a new era in x-ray astronomy, but there remains a need for instrumentation that can provide higher spectral resolution with high throughput in the Fe-K band (around 6 keV) and can enable imaging spectroscopy of extended sources, such as supernova remnants and galaxy clusters. The instrumentation needed is a broad-band imaging spectrometer - basically an x-ray camera that can distinguish tens of thousands of x-ray colors. The potential benefits to astrophysics of using a low-temperature calorimeter to determine the energy of an incident x-ray photon via measurement of a small change in temperature was first articulated by S. H. Moseley over two decades ago. In the time since, technological progress has been steady, though full realization in an orbiting x-ray telescope is still awaited. A low-temperature calorimeter can be characterized by the type of thermometer it uses, and three types presently dominate the field. The first two types are temperature-sensitive resistors - semiconductors in the metal-insulator transition and superconductors operated in the superconducting-normal transition. The third type uses a paramagnetic thermometer. These types can be considered the three generations of x-ray calorimeters; by now each has demonstrated a resolving power of 2000 at 6 keV, but only a semiconductor calorimeter system has been developed to spaceflight readiness. The Soft X-ray Spectrometer on Astro-H, expected to launch in 2013, will use an array of silicon thermistors with I-IgTe x-ray absorbers that will operate at 50 mK. Both the semiconductor and superconductor calorimeters have been implemented in small arrays, kilo-pixel arrays of the superconducting calorimeters are just now being produced, and it is anticipated that much larger arrays will require the non-dissipative advantage of magnetic thermometers.

  9. Superconductivity

    CERN Document Server

    Ketterson, John B

    2008-01-01

    Conceived as the definitive reference in a classic and important field of modern physics, this extensive and comprehensive handbook systematically reviews the basic physics, theory and recent advances in the field of superconductivity. Leading researchers, including Nobel laureates, describe the state-of-the-art in conventional and unconventional superconductors at a particularly opportune time, as new experimental techniques and field-theoretical methods have emerged. In addition to full-coverage of novel materials and underlying mechanisms, the handbook reflects continued intense research into electron-phone based superconductivity. Considerable attention is devoted to high-Tc superconductivity, novel superconductivity, including triplet pairing in the ruthenates, novel superconductors, such as heavy-Fermion metals and organic materials, and also granular superconductors. What’s more, several contributions address superconductors with impurities and nanostructured superconductors. Important new results on...

  10. A high resolution gamma-ray spectrometer based on superconducting microcalorimeters

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, D. A.; Horansky, R. D. [National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); University of Denver, Denver, Colorado 80208 (United States); Schmidt, D. R.; Doriese, W. B.; Fowler, J. W.; Kotsubo, V.; Mates, J. A. B. [National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); University of Colorado, Boulder, Colorado 80309 (United States); Hoover, A. S.; Winkler, R.; Rabin, M. W. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Alpert, B. K.; Beall, J. A.; Fitzgerald, C. P.; Hilton, G. C.; Irwin, K. D.; O' Neil, G. C.; Reintsema, C. D.; Schima, F. J.; Swetz, D. S.; Vale, L. R. [National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); and others

    2012-09-15

    Improvements in superconductor device fabrication, detector hybridization techniques, and superconducting quantum interference device readout have made square-centimeter-sized arrays of gamma-ray microcalorimeters, based on transition-edge sensors (TESs), possible. At these collecting areas, gamma microcalorimeters can utilize their unprecedented energy resolution to perform spectroscopy in a number of applications that are limited by closely-spaced spectral peaks, for example, the nondestructive analysis of nuclear materials. We have built a 256 pixel spectrometer with an average full-width-at-half-maximum energy resolution of 53 eV at 97 keV, a useable dynamic range above 400 keV, and a collecting area of 5 cm{sup 2}. We have demonstrated multiplexed readout of the full 256 pixel array with 236 of the pixels (91%) giving spectroscopic data. This is the largest multiplexed array of TES microcalorimeters to date. This paper will review the spectrometer, highlighting the instrument design, detector fabrication, readout, operation of the instrument, and data processing. Further, we describe the characterization and performance of the newest 256 pixel array.

  11. Superconductivity revisited

    CERN Document Server

    Dougherty, Ralph

    2013-01-01

    While the macroscopic phenomenon of superconductivity is well known and in practical use worldwide in many industries, including MRIs in medical diagnostics, the current theoretical paradigm for superconductivity (BCS theory) suffers from a number of limitations, not the least of which is an adequate explanation of high temperature superconductivity. This book reviews the current theory and its limitations and suggests new ideas and approaches in addressing these issues. The central objective of the book is to develop a new, coherent, understandable theory of superconductivity directly based on molecular quantum mechanics.

  12. High field superconducting magnets

    Science.gov (United States)

    Hait, Thomas P. (Inventor); Shirron, Peter J. (Inventor)

    2011-01-01

    A superconducting magnet includes an insulating layer disposed about the surface of a mandrel; a superconducting wire wound in adjacent turns about the mandrel to form the superconducting magnet, wherein the superconducting wire is in thermal communication with the mandrel, and the superconducting magnet has a field-to-current ratio equal to or greater than 1.1 Tesla per Ampere; a thermally conductive potting material configured to fill interstices between the adjacent turns, wherein the thermally conductive potting material and the superconducting wire provide a path for dissipation of heat; and a voltage limiting device disposed across each end of the superconducting wire, wherein the voltage limiting device is configured to prevent a voltage excursion across the superconducting wire during quench of the superconducting magnet.

  13. Aperiodic superconducting phase boundary of periodic micronetworks in a magnetic field

    International Nuclear Information System (INIS)

    Nori, F.; Niu, Q.

    1988-01-01

    We study flux quantization in periodic arrays with two elementary cells having an irrational ratio of areas. In particular, we calculate the superconducting-normal phase boundary T/sub c/(H) and we analyze the origin of its overall and fine structure as a function of the network size. We discuss our theoretical results, exploiting the electronic tight-binding analogy to the Ginzburg-Landau equations, and compare them with the experimental ones

  14. Bolometer Results in the Long-Microwave-Heated WEGA Stellarator

    International Nuclear Information System (INIS)

    Zhang, D.; Otte, M.; Giannone, L.

    2006-01-01

    A 12 channel bolometer camera based on a gold foil absorber has been installed on the WEGA stellarator to measure the radiation power losses of the plasma. The measured total radiation power is typically less than 30% of the ECRH input power. However, this radiated power fraction depends on the ECRH input power, the magnetic configuration and the field strength as well as the working gas. For separatrix-bounded configurations, core-peaked radiation intensity profiles are usually detected, while in a limiter-configuration they are flatter, broader and more asymmetric. In addition, significant radiation originating from the SOL region is measured for all the cases studied. The SOL radiation changes with changing the plasma-wave interaction region, indicating a strong correlation between radiation and power deposition. Under the WEGA-plasma conditions (Te<10 eV), it is considered that the radiation profile reflects the plasma pressure associated with the power deposition distribution of the ECRH

  15. Bolometer Results in the Long-Microwave-Heated WEGA Stellarator

    Science.gov (United States)

    Zhang, D.; Otte, M.; Giannone, L.

    2006-01-01

    A 12 channel bolometer camera based on a gold foil absorber has been installed on the WEGA stellarator to measure the radiation power losses of the plasma. The measured total radiation power is typically less than 30% of the ECRH input power. However, this radiated power fraction depends on the ECRH input power, the magnetic configuration and the field strength as well as the working gas. For separatrix-bounded configurations, core-peaked radiation intensity profiles are usually detected, while in a limiter-configuration they are flatter, broader and more asymmetric. In addition, significant radiation originating from the SOL region is measured for all the cases studied. The SOL radiation changes with changing the plasma-wave interaction region, indicating a strong correlation between radiation and power deposition. Under the WEGA-plasma conditions (Te<10 eV), it is considered that the radiation profile reflects the plasma pressure associated with the power deposition distribution of the ECRH.

  16. Superconducting focusing quadrupoles for heavy ion fusion experiments

    Energy Technology Data Exchange (ETDEWEB)

    Sabbi, G.L.; Faltens, A.; Leitner, M.; Lietzke, A.; Seidl, P.; Barnard, J.; Lund, S.; Martovetsky, N.; Gung, C.; Minervini, J.; Radovinsky, A.; Schultz, J.; Meinke, R.

    2003-05-01

    The Heavy Ion Fusion (HIF) Program is developing superconducting focusing magnets for both near-term experiments and future driver accelerators. In particular, single bore quadrupoles have been fabricated and tested for use in the High Current Experiment (HCX) at Lawrence Berkeley National Laboratory (LBNL). The next steps involve the development of magnets for the planned Integrated Beam Experiment (IBX) and the fabrication of the first prototype multi-beam focusing arrays for fusion driver accelerators. The status of the magnet R&D program is reported, including experimental requirements, design issues and test results.

  17. The ramp rate dependence of the sextupole field in superconducting dipoles

    International Nuclear Information System (INIS)

    Ghosh, A.K.; Robins, K.E.; Sampson, W.B.

    1993-01-01

    Sextupole components are induced in the magnetic field of superconducting dipoles when the current is changed. The magnitude of this effect depends on the rate of change of field, the strand-to-strand resistance in the superconducting cable, and the twist pitch of the wire. Ramp rate measurements have been made on a number of SSC dipoles wound from conductors with different interstrand resistances. The technique employed uses an array of Hall probes sensitive to the sextupole field and can measure the difference for field increasing or decreasing as a function of axial position. Magnets with very low interstrand resistance exhibit a large axial oscillation in the sextupole field between up and down ramps which is rate dependent When the strand resistance is high the amplitude of this oscillation is almost independent of ramp rate

  18. Superconducting cavity driving with FPGA controller

    Energy Technology Data Exchange (ETDEWEB)

    Czarski, T.; Koprek, W.; Pozniak, K.T.; Romaniuk, R.S. [Warsaw Univ. of Technology (Poland); Simrock, S.; Brand, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Chase, B.; Carcagno, R.; Cancelo, G. [Fermi National Accelerator Lab., Batavia, IL (United States); Koeth, T.W. [Rutgers - the State Univ. of New Jersey, NJ (United States)

    2006-07-01

    The digital control of several superconducting cavities for a linear accelerator is presented. The laboratory setup of the CHECHIA cavity and ACC1 module of the VU-FEL TTF in DESY-Hamburg have both been driven by a Field Programmable Gate Array (FPGA) based system. Additionally, a single 9-cell TESLA Superconducting cavity of the FNPL Photo Injector at FERMILAB has been remotely controlled from WUT-ISE laboratory with the support of the DESY team using the same FPGA control system. These experiments focused attention on the general recognition of the cavity features and projected control methods. An electrical model of the resonator was taken as a starting point. Calibration of the signal path is considered key in preparation for the efficient driving of a cavity. Identification of the resonator parameters has been proven to be a successful approach in achieving required performance; i.e. driving on resonance during filling and field stabilization during flattop time while requiring reasonable levels of power consumption. Feed-forward and feedback modes were successfully applied in operating the cavities. Representative results of the experiments are presented for different levels of the cavity field gradient. (orig.)

  19. Superconducting cavity driving with FPGA controller

    International Nuclear Information System (INIS)

    Czarski, T.; Koprek, W.; Pozniak, K.T.; Romaniuk, R.S.; Simrock, S.; Brand, A.; Chase, B.; Carcagno, R.; Cancelo, G.; Koeth, T.W.

    2006-01-01

    The digital control of several superconducting cavities for a linear accelerator is presented. The laboratory setup of the CHECHIA cavity and ACC1 module of the VU-FEL TTF in DESY-Hamburg have both been driven by a Field Programmable Gate Array (FPGA) based system. Additionally, a single 9-cell TESLA Superconducting cavity of the FNPL Photo Injector at FERMILAB has been remotely controlled from WUT-ISE laboratory with the support of the DESY team using the same FPGA control system. These experiments focused attention on the general recognition of the cavity features and projected control methods. An electrical model of the resonator was taken as a starting point. Calibration of the signal path is considered key in preparation for the efficient driving of a cavity. Identification of the resonator parameters has been proven to be a successful approach in achieving required performance; i.e. driving on resonance during filling and field stabilization during flattop time while requiring reasonable levels of power consumption. Feed-forward and feedback modes were successfully applied in operating the cavities. Representative results of the experiments are presented for different levels of the cavity field gradient. (orig.)

  20. Superconducting rf development at ATLAS

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K.W.; Kedzie, M.; Clifft, B.E. [Argonne National Lab., IL (United States); Roy, A.; Potukuchi, P. [Nuclear Science Centre, New Delhi (India); Givens, J.; Potter, J.; Crandall, K. [AccSys Technology, Inc., Pleasanton, CA (United States); Added, N. [Sao Paulo Univ., SP (Brazil)

    1993-12-31

    The ATLAS superconducting heavy-ion linac began operation in 1978 and has operated nearly continuously since that time, while undergoing a series of upgrades and expansions, the most recent being the ``uranium upgrade`` completed earlier this year and described below. In its present configuration the ATLAS linac consists of an array of 64 resonant cavities operating from 48 to 145 MHz, which match a range of particle velocities .007 < {beta} = v/c < .2. The linac provides approximately 50 MV of effective accelerating potential for ions of q/m > 1/10 over the entire periodic table. Delivered beams include 5 {minus} 7 pnA of {sup 238}U{sup 39+} at 1535 MeV. At present more than 10{sup 6} cavity-hours of operation at surface electric fields of 15 MV/m have been accumulated. Superconducting structure development at ATLAS is aimed at improving the cost/performance of existing low velocity structures both for possible future ATLAS upgrades, and also for heavy-ion linacs at other institutions. An application of particular current interest is to develop structures suitable for accelerating radioactive ion beams. Such structures must accelerate very low charge to mass ratio beams and must also have very large transverse acceptance.

  1. Superconductivity in gallium-implanted silicon; Supraleitung in Gallium-implantiertem Silizium

    Energy Technology Data Exchange (ETDEWEB)

    Skrotzki, Richard

    2016-07-12

    The following thesis is devoted to the electrical characterization of 10 nm thin layers consisting of amorphous Ga nanoclusters embedded in Ga-doped polycrystalline Si. The preparation of the layers is realized via ion implantation in Si wafers plus subsequent thermal annealing. Electrical-transport measurements in magnetic fields of up to 50 T show that the layers undergo two structural superconductor-insulator transitions upon variation of the annealing parameters. Structural analyzes based on TEM investigations reveal an underlying transformation of the size and distance of the clusters. This influences the interplay of the superconducting cluster coupling and capacitive charging energy as well as the extent of thermal and quantum fluctuations. In the superconducting regime (Tc ∼ 7 K) a double-reentrant phenomenon is observed. Here, magnetic fields of several Tesla facilitate superconductivity in an anisotropic way. A qualitative explanation is given via a self-developed theoretical model based on phase-slip events for Josephson-junction arrays. With respect to applications regarding sensor technology and quantum logic circuits the layers are successfully micro- and nanostructured via photolithography and FIB. This allows for the first observation of the Little-Parks effect in a nanostructure of amorphous Ga.

  2. Superconductivity in Medicine

    Science.gov (United States)

    Alonso, Jose R.; Antaya, Timothy A.

    2012-01-01

    Superconductivity is playing an increasingly important role in advanced medical technologies. Compact superconducting cyclotrons are emerging as powerful tools for external beam therapy with protons and carbon ions, and offer advantages of cost and size reduction in isotope production as well. Superconducting magnets in isocentric gantries reduce their size and weight to practical proportions. In diagnostic imaging, superconducting magnets have been crucial for the successful clinical implementation of magnetic resonance imaging. This article introduces each of those areas and describes the role which superconductivity is playing in them.

  3. Superconductivity in technology

    International Nuclear Information System (INIS)

    Komarek, P.

    1976-01-01

    Physics, especially high energy physics and solid state physics was the first area in which superconducting magnets were used but in the long run, the most extensive application of superconductivity will probably be in energy technology. Superconducting power transmission cables, magnets for energy conversion in superconducting electrical machines, MHD-generators and fusion reactors and magnets for energy storage are being investigated. Magnets for fusion reactors will have particularly large physical dimensions, which means that much development effort is still needed, for there is no economic alternative. Superconducting surfaces in radio frequency cavities can give Q-values up to a factor of 10 6 higher than those of conventional resonators. Particle accelerators are the important application. And for telecommunication, simple coaxial superconducting radio frequency cables seem promising. The tunnel effect in superconducting junctions is now being developed commercially for sensitive magnetometers and may soon possibly feature in the memory cells of computer devices. Hence superconductivity can play an important role in the technological world, solving physical and technological problems and showing economic advantages as compared with possible conventional techniques, bearing also in mind the importance of reliability and safety. (author)

  4. Distributed Read-out Imaging Device array for astronomical observations in UV/VIS

    NARCIS (Netherlands)

    Hijmering, R.A.

    2009-01-01

    STJ (Superconducting Tunneling Junctions) are being developed as spectro-photometers in wavelengths ranging from the NIR to X-rays. 10x12 arrays of STJs have already been successfully used as optical imaging spectrometers with the S-Cam 3, on the William Hershel Telescope on La Palma and on the

  5. Cryogenic photodetectors

    Science.gov (United States)

    Chardin, G.

    2000-03-01

    Some of the most significant developments in cryogenic photodetectors are presented. In particular, the main characteristics of microbolometers involving Transition Edge- and NTD-sensors and offering resolutions of a few eV in the keV range, superconducting tunnel junction detectors with resolutions of the order of 10 eV or offering position sensitivity, and infrared bolometers with recent developments towards matrix detectors are discussed. Some of the recent achievements using large mass bolometers for gamma and neutron discriminating detectors, and future prospects of single photon detection in the far infrared using Single Electron Transistor devices are also presented.

  6. Cryogenic photodetectors

    CERN Document Server

    Chardin, G

    2000-01-01

    Some of the most significant developments in cryogenic photodetectors are presented. In particular, the main characteristics of microbolometers involving Transition Edge- and NTD-sensors and offering resolutions of a few eV in the keV range, superconducting tunnel junction detectors with resolutions of the order of 10 eV or offering position sensitivity, and infrared bolometers with recent developments towards matrix detectors are discussed. Some of the recent achievements using large mass bolometers for gamma and neutron discriminating detectors, and future prospects of single photon detection in the far infrared using Single Electron Transistor devices are also presented.

  7. First scintillating bolometer tests of a CLYMENE R&D on Li2MoO4 scintillators towards a large-scale double-beta decay experiment

    Science.gov (United States)

    Buşe, G.; Giuliani, A.; de Marcillac, P.; Marnieros, S.; Nones, C.; Novati, V.; Olivieri, E.; Poda, D. V.; Redon, T.; Sand, J.-B.; Veber, P.; Velázquez, M.; Zolotarova, A. S.

    2018-05-01

    A new R&D on lithium molybdate scintillators has begun within a project CLYMENE (Czochralski growth of Li2MoO4 crYstals for the scintillating boloMeters used in the rare EveNts sEarches). One of the main goals of the CLYMENE is a realization of a Li2MoO4 crystal growth line to be complementary to the one recently developed by LUMINEU in view of a mass production capacity for CUPID, a next-generation tonne-scale bolometric experiment to search for neutrinoless double-beta decay. In the present paper we report the investigation of performance and radiopurity of 158-g and 13.5-g scintillating bolometers based on a first large-mass (230 g) Li2MoO4 crystal scintillator developed within the CLYMENE project. In particular, a good energy resolution (2-7 keV FWHM in the energy range of 0.2-5 MeV), one of the highest light yield (0.97 keV/MeV) amongst Li2MoO4 scintillating bolometers, an efficient alpha particles discrimination (10 σ) and potentially low internal radioactive contamination (below 0.2-0.3 mBq/kg of U/Th, but 1.4 mBq/kg of 210Po) demonstrate prospects of the CLYMENE in the development of high quality and radiopure Li2MoO4 scintillators for CUPID.

  8. Development of Superconducting Focusing Quadrupoles for Heavy Ion Drivers

    Energy Technology Data Exchange (ETDEWEB)

    Martovetsky, N; Manahan, R; Lietzke, A F

    2001-09-10

    Heavy Ion Fusion (HIF) is exploring a promising path to a practical inertial-confinement fusion reactor. The associated heavy ion driver will require a large number of focusing quadrupole magnets. A concept for a superconducting quadrupole array, using many simple racetrack coils, was developed at LLNL. Two, single-bore quadrupole prototypes of the same design, with distinctly different conductor, were designed, built, and tested. Both prototypes reached their short sample currents with little or no training. Magnet design, and test results, are presented and discussed.

  9. Design and characterization of a prototype divertor viewing infrared video bolometer for NSTX-U

    Energy Technology Data Exchange (ETDEWEB)

    Eden, G. G. van; Morgan, T. W. [Dutch Institute for Fundamental Energy Research, 5612 AJ Eindhoven (Netherlands); Reinke, M. L.; Gray, T. K.; Lore, J. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Peterson, B. J.; Mukai, K. [National Institute for Fusion Science, Toki 509-5292 (Japan); Delgado-Aparicio, L. F.; Jaworski, M. A. [Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States); Sano, R. [National Institutes for Quantum and Radiological Science and Technology, Naka 311-0193 (Japan); Pandya, S. N. [Institute for Plasma Research, Bhat Village, Gandhinagar, 382428 Gujarat (India)

    2016-11-15

    The InfraRed Video Bolometer (IRVB) is a powerful tool to measure radiated power in magnetically confined plasmas due to its ability to obtain 2D images of plasma emission using a technique that is compatible with the fusion nuclear environment. A prototype IRVB has been developed and installed on NSTX-U to view the lower divertor. The IRVB is a pinhole camera which images radiation from the plasma onto a 2.5 μm thick, 9 × 7 cm{sup 2} Pt foil and monitors the resulting spatio-temporal temperature evolution using an IR camera. The power flux incident on the foil is calculated by solving the 2D+time heat diffusion equation, using the foil’s calibrated thermal properties. An optimized, high frame rate IRVB, is quantitatively compared to results from a resistive bolometer on the bench using a modulated 405 nm laser beam with variable power density and square wave modulation from 0.2 Hz to 250 Hz. The design of the NSTX-U system and benchtop characterization are presented where signal-to-noise ratios are assessed using three different IR cameras: FLIR A655sc, FLIR A6751sc, and SBF-161. The sensitivity of the IRVB equipped with the SBF-161 camera is found to be high enough to measure radiation features in the NSTX-U lower divertor as estimated using SOLPS modeling. The optimized IRVB has a frame rate up to 50 Hz, high enough to distinguish radiation during edge-localized-modes (ELMs) from that between ELMs.

  10. Current distribution inside Rutherford-type superconducting cables and impact on performance of LHC dipoles

    CERN Document Server

    Schreiner, T

    2002-01-01

    The windings of high--field superconducting accelerator magnets are usually made of Rutherford--type cables. The magnetic field distribution along the axis of such magnets exhibits a periodic modulation with a wavelength equal to the twist pitch length of the cable used in the winding. Such a Periodic Field Pattern (PFP) has already been observed in number of superconducting accelerator magnets. Additional unbalanced currents in individual strands of the cable appear to be causing this effect. The present thesis describes the investigation of the PFPs performed with a Hall probes array inserted inside the aperture of the LHC superconducting dipoles, both in the small--scale model magnets with a length of one meter and in full--scale prototypes and pre--series magnets with fifteen meters of length. The amplitude and the time dependence of this periodic field oscillation have been studied as a function of the magnet current history. One of the main parameters influencing the properties of the PFP is the cross--...

  11. Bolometer tomography at the density limit of the HDH mode in the W7-AS stellarator

    International Nuclear Information System (INIS)

    Giannone, L; Brakel, R; Burhenn, R; Ehmler, H; Feng, Y; Grigull, P; McCormick, K; Wagner, F; Baldzuhn, J; Igitkhanov, Y; Knauer, J; Nishimura, K; Pasch, E; Peterson, B J; Ramasubramanian, N; Rust, N; Weller, A; Werner, A

    2003-01-01

    The installation of divertor plates in the W7-AS stellarator has allowed attainment of a high energy confinement regime at high density, where the radiation profiles reached steady state. In this regime, the radial profile of the radiated power is hollow. Raising the density to the point where the radiated power approached the input power led to plasma detachment and a decrease in diamagnetic energy. This defines the density limit in a stellarator and a scaling law for this maximum density can be heuristically derived on the basis of power balance considerations. The installation of two bolometer cameras away from the divertor plates and three bolometer cameras in the vicinity of the divertor plates has provided insight into the features of high density operation of a divertor in a stellarator. In the main chamber, tomographic inversion at the density limit has shown that a poloidally asymmetric radiation profile developed as the density limit was approached. In the divertor, radiation in front of the divertor plates occurred while the plasma was attached and this radiation zone vanished at plasma detachment. Steady state discharges of up to 1.5 s have been achieved for neutral beam injection power of up to 2 MW. A precursor to a spontaneous transition out of the high confinement regime has been identified

  12. Superconducting Thin-Film Interconnects for Cryogenic Photon Detector Arrays, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Advanced imaging spectrometers for x-ray astronomy will require significant improvements in the high density interconnects between the detector arrays and the first...

  13. Understanding and application of superconducting materials

    International Nuclear Information System (INIS)

    Moon, Byeong Mu; Lee, Chun Heung

    1997-02-01

    This book deals with superconducting materials, which contains from basic theory to application of superconducting materials. The contents of this book are mystery of superconducting materials, properties of superconducting materials, thermodynamics of superconducting materials, theoretical background of superconducting materials, tunnelling and quantum interference, classification and properties of superconducting materials, high temperature superconducting materials, production and analysis of superconducting materials and application of superconducting materials.

  14. Submicron superconducting structures

    International Nuclear Information System (INIS)

    Golovashkin, A.I.; Lykov, A.N.

    1986-01-01

    An overview of works concerning superconducting structures of submicron dimensions and a system of such structures is given. It is noted that usage of the above structures in superconducting microelectronics permits, first, to increase the element packing density, to decrease the signal transmission time, capacity, power dissipated in high-frequency applications. Secondly, negligible coherence length in transition metals, their alloys and high-temperature compounds also restrict the dimensions of superconducting weak couplings when the 'classical' Josephson effect is displayed. The most effective methods for production of submicron superconducting structures are the following: lithography, double scribering. Recently the systems of superconducting submicron elements are extensively studied. It is shown that such systems can be phased by magnetic field

  15. Transition-edge sensor imaging arrays for astrophysics applications

    Science.gov (United States)

    Burney, Jennifer Anne

    Many interesting objects in our universe currently elude observation in the optical band: they are too faint or they vary rapidly and thus any structure in their radiation is lost over the period of an exposure. Conventional photon detectors cannot simultaneously provide energy resolution and time-stamping of individual photons at fast rates. Superconducting detectors have recently made the possibility of simultaneous photon counting, imaging, and energy resolution a reality. Our research group has pioneered the use of one such detector, the Transition-Edge Sensor (TES). TES physics is simple and elegant. A thin superconducting film, biased at its critical temperature, can act as a particle detector: an incident particle deposits energy and drives the film into its superconducting-normal transition. By inductively coupling the detector to a SQUID amplifier circuit, this resistance change can be read out as a current pulse, and its energy deduced by integrating over the pulse. TESs can be used to accurately time-stamp (to 0.1 [mu]s) and energy-resolve (0.15 eV at 1.6 eV) near-IR/visible/near-UV photons at rates of 30~kHz. The first astronomical observations using fiber-coupled detectors were made at the Stanford Student Observatory 0.6~m telescope in 1999. Further observations of the Crab Pulsar from the 107" telescope at the University of Texas McDonald Observatory showed rapid phase variations over the near-IR/visible/near-UV band. These preliminary observations provided a glimpse into a new realm of observations of pulsars, binary systems, and accreting black holes promised by TES arrays. This thesis describes the development, characterization, and preliminary use of the first camera system based on Transition-Edge Sensors. While single-device operation is relatively well-understood, the operation of a full imaging array poses significant challenges. This thesis addresses all aspects related to the creation and characterization of this cryogenic imaging

  16. Microwave oscillator using arrays of long Josephson junctions

    International Nuclear Information System (INIS)

    Pagano, S.; Monaco, R.; Costabile, G.

    1989-01-01

    The authors report on measurements performed on integrated superconducting devices based on arrays of long Josephson tunnel junctions operating in the resonant fluxon oscillation regime (i.e. biased on the Zero Field Steps). The electromagnetic coupling among the junction causes a mutual phase-locking of the fluxon oscillations with a corresponding increase of the emitted power and a decrease of the signal linewidth. This phase-locked state can be controlled by means of an external dc bias current and magnetic field. The effect of the generated microwave signal has been observed on a small Josephson tunnel junction coupled to the array via a microstrip transmission line. The feasibility of the reported devices as local oscillators in an integrated microwave Josephson receiver is discussed

  17. Academic training: Applied superconductivity

    CERN Multimedia

    2007-01-01

    LECTURE SERIES 17, 18, 19 January from 11.00 to 12.00 hrs Council Room, Bldg 503 Applied Superconductivity : Theory, superconducting Materials and applications E. PALMIERI/INFN, Padova, Italy When hearing about persistent currents recirculating for several years in a superconducting loop without any appreciable decay, one realizes that we are dealing with a phenomenon which in nature is the closest known to the perpetual motion. Zero resistivity and perfect diamagnetism in Mercury at 4.2 K, the breakthrough during 75 years of several hundreds of superconducting materials, the revolution of the "liquid Nitrogen superconductivity"; the discovery of still a binary compound becoming superconducting at 40 K and the subsequent re-exploration of the already known superconducting materials: Nature discloses drop by drop its intimate secrets and nobody can exclude that the last final surprise must still come. After an overview of phenomenology and basic theory of superconductivity, the lectures for this a...

  18. A Hot-electron Direct Detector for Radioastronomy

    Science.gov (United States)

    Karasik, B. S.; McGrath, W. R.; LeDuc, H. G.

    2000-01-01

    A new approach is proposed to improve the sensitivity of direct-detection bolometers. The idea is to adjust a speed of the thermal relaxation of hot-electrons in a nanometer size normal metal or superconductive transition edge bolometer by controlling the elastic electron mean free path. If the bolometer contacts are made of a superconductor with high critical temperature then the thermal diffusion into the contacts is absent because of the Andreev's reflection and the electron-phonon relaxation is the only mechanism for heat removal. The relaxation rate should behave as 7(exp 4)l at subkelvin temperatures (l is the electron elastic mean free path) and can be reduced by factor of 10 - 100 by decreasing l. Then an antenna- or waveguide-coupled bolometer with a time constant approx. 10(exp -3) to 10(exp -5) S at T approx. = 0.1 - 0.3 K will exhibit photon-noise limited performance in millimeter and subn-millimeter range. The bolometer will have a figure-of-merit NEk square root of tau approx. = 10(exp -22) 10(exp -21) W/Hz at 100 mK which is 10(exp 3) times smaller than that of a state-of-the-art bolometer. This will allow for a tremendous increase in speed which will have a significant impact for observational mapping applications. Alternatively, the bolometer could operate at higher temperature with still superior sensitivity This research was performed by the Center for Space Microelectronics Technology, JPL, California Institute of Technology, under the contract for NASA.

  19. The state of superconductivity

    International Nuclear Information System (INIS)

    Clark, T.D.

    1981-01-01

    The present status of applications based on the phenomena of superconductivity are reviewed. Superconducting materials, large scale applications, the Josephson effect and its applications, and superconductivity in instrumentation, are considered. The influence that superconductivity has had on modern theories of elementary particles, such as gauge symmetry breaking, is discussed. (U.K.)

  20. Superconductivity - applications

    International Nuclear Information System (INIS)

    The paper deals with the following subjects: 1) Electronics and high-frequency technology, 2) Superconductors for energy technology, 3) Superconducting magnets and their applications, 4) Electric machinery, 5) Superconducting cables. (WBU) [de

  1. Basic Study of Superconductive Actuator

    OpenAIRE

    涌井, 和也; 荻原, 宏康

    2000-01-01

    There are two kinds of electromagnetic propulsion ships : a superconductive electromagnetic propulsion ship and a superconductive electricity propulsion ship. A superconductive electromagnetic propulsion ship uses the electromagnetic force (Lorenz force) by the interaction between a magnetic field and a electric current. On the other hand, a superconductive electricity propulsion ship uses screws driven by a superconductive motor. A superconductive propulsion ship technique has the merits of ...

  2. 100 years of superconductivity

    CERN Document Server

    Rogalla, Horst

    2011-01-01

    Even a hundred years after its discovery, superconductivity continues to bring us new surprises, from superconducting magnets used in MRI to quantum detectors in electronics. 100 Years of Superconductivity presents a comprehensive collection of topics on nearly all the subdisciplines of superconductivity. Tracing the historical developments in superconductivity, the book includes contributions from many pioneers who are responsible for important steps forward in the field.The text first discusses interesting stories of the discovery and gradual progress of theory and experimentation. Emphasizi

  3. Superconducting current in a bisoliton superconductivity model

    International Nuclear Information System (INIS)

    Ermakov, V.N.; Kruchinin, S.P.; Ponezha, E.A.

    1991-01-01

    It is shown that the transition into a superconducting state with the current which is described by a bisoliton superconductivity model is accompanied by the deformation of the spectrum of one-particle states of the current carriers. The deformation value is proportional to the conducting current force. The residuaby resistance in such state is absent

  4. Coexistence of magnetism and superconductivity in the hole doped FeAs-based superconducting compound

    International Nuclear Information System (INIS)

    Lu, T.P.; Wu, C.C.; Chou, W.H.; Lan, M.D.

    2010-01-01

    The magnetic and superconducting properties of the Sm-doped FeAs-based superconducting compound were investigated under wide ranges of temperature and magnetic field. After the systematical magnetic ion substitution, the superconducting transition temperature decreases with increasing magnetic moment. The hysteresis loop of the La 0.87-x Sm x Sr 0.13 FeAsO sample shows a superconducting hysteresis and a paramagnetic background signal. The paramagnetic signal is mainly attributed to the Sm moments. The experiment demonstrates that the coexistence of magnetism and superconductivity in the hole doped FeAs-based superconducting compounds is possible. Unlike the electron doped FeAs-based superconducting compounds SmFeAsOF, the hole doped superconductivity is degraded by the substitution of La by Sm. The hole-doped and electron-doped sides are not symmetric.

  5. Characterization and Modeling of Superconducting Josephson Junction Arrays at Low Voltage and Liquid Helium Temperatures

    Science.gov (United States)

    2016-09-01

    both from SSC Pacific) and Marc Tukeman, Chuck Vinson and Mr. Mark Flemon with the procurement process . We acknowledge Deep Gupta, Saad Sarwana, and...superconductor-ionic quantum memory and computation devices. iv CONTENTS EXECUTIVE SUMMARY...Josephson effect makes these measurements useful for characterization and calibration of superconducting quantum memory and computational devices

  6. Quadrupolar interactions in non-cubic crystal and related extra heat capacities. Possible effects on a sapphire bolometer

    Energy Technology Data Exchange (ETDEWEB)

    Bassou, M. [Tunis Univ. (Tunisia)]|[CEA/DSM/DRECAM/SPEC, Gif-wur-Yvette (France); Rotter, M. [Karlova Univ., Prague (Czech Republic)]|[CEA/DSM/DRECAM/SPEC, Gif-wur-Yvette (France); Bernier, M. [CEA/DSM/DRECAM/SPEC, Gif-wur-Yvette (France); Chapellier, M. [CEA/DSM/DRECAM/SPEC, Gif-wur-Yvette (France)

    1996-02-11

    It is shown that in a non-cubic crystal, the extra heat capacity due to quadrupolar interaction of nuclear spins >1/2 could be much bigger than the phonon heat capacity when the temperature decreases. The possible coupling between quadrupolar and phonon heat reservoir via paramagnetic impurities is stressed. A NMR experiment done on sapphire is presented with an evaluation of the coupling between the two reservoirs and its consequence on the performance of the bolometer. (orig.).

  7. Quadrupolar interactions in non-cubic crystal and related extra heat capacities. Possible effects on a sapphire bolometer

    International Nuclear Information System (INIS)

    Bassou, M.; Rotter, M.; Bernier, M.; Chapellier, M.

    1996-01-01

    It is shown that in a non-cubic crystal, the extra heat capacity due to quadrupolar interaction of nuclear spins >1/2 could be much bigger than the phonon heat capacity when the temperature decreases. The possible coupling between quadrupolar and phonon heat reservoir via paramagnetic impurities is stressed. A NMR experiment done on sapphire is presented with an evaluation of the coupling between the two reservoirs and its consequence on the performance of the bolometer. (orig.)

  8. Superconducting accelerating structures for very low velocity ion beams

    Directory of Open Access Journals (Sweden)

    J. Xu

    2008-03-01

    Full Text Available This paper presents designs for four types of very-low-velocity superconducting (SC accelerating cavity capable of providing several MV of accelerating potential per cavity, and suitable for particle velocities in the range 0.006Superconducting TEM-class cavities have been widely applied to cw acceleration of ion beams. SC linacs can be formed as an array of independently phased cavities, enabling a variable velocity profile to maximize the output energy for each of a number of different ion species. Several laboratories in the U.S. and Europe are planning exotic beam facilities based on SC linacs. The cavity designs presented here are intended for the front end of such linacs, particularly for the postacceleration of rare isotopes of low charge state. Several types of SC cavities have been developed recently to cover particle velocities above 0.06c. Superconducting four-gap quarter-wave resonators for velocities 0.008<β=v/c<0.05 were developed about two decades ago and have been successfully operated at the ATLAS SC linac at Argonne National Laboratory. Since that time, progress in simulation tools, cavity fabrication, and processing have increased SC cavity gradients by a factor of 3–4. This paper applies these tools to optimize the design of a four-gap quarter-wave resonator for exotic beam facilities and other low-velocity applications.

  9. Superconducting accelerating structures for very low velocity ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Xu, J.; Shepard, K.W.; Ostroumov, P.N.; Fuerst, J.D.; Waldschmidt, G.; /Argonne; Gonin, I.V.; /Fermilab

    2008-01-01

    This paper presents designs for four types of very-low-velocity superconducting accelerating cavity capable of providing several MV of accelerating potential per cavity, and suitable for particle velocities in the range 0.006 < v/c < 0.06. Superconducting TEM-class cavities have been widely applied to CW acceleration of ion beams. SC linacs can be formed as an array of independently-phased cavities, enabling a variable velocity profile to maximize the output energy for each of a number of different ion species. Several laboratories in the US and Europe are planning exotic beam facilities based on SC linacs. The cavity designs presented here are intended for the front-end of such linacs, particularly for the post-acceleration of rare isotopes of low charge state. Several types of SC cavities have been developed recently to cover particle velocities above 0.06c. Superconducting four-gap quarter-wave resonators for velocities 0.008 < {beta} = v/c < 0.05 were developed about two decades ago and have been successfully operated at the ATLAS SC linac at Argonne National Laboratory. Since that time, progress in simulation tools, cavity fabrication and processing have increased SC cavity gradients by a factor of 3-4. This paper applies these tools to optimize the design of a four-gap quarter-wave resonator for exotic beam facilities and other low-velocity applications.

  10. Complex envelope control of pulsed accelerating fields in superconducting cavities

    CERN Document Server

    Czarski, T

    2010-01-01

    A digital control system for superconducting cavities of a linear accelerator is presented in this work. FPGA (Field Programmable Gate Arrays) based controller, managed by MATLAB, was developed to investigate a novel firmware implementation. The LLRF - Low Level Radio Frequency system for FLASH project in DESY is introduced. Essential modeling of a cavity resonator with signal and power analysis is considered as a key approach to the control methods. An electrical model is represented by the non-stationary state space equation for the complex envelope of the cavity voltage driven by the current generator and the beam loading. The electromechanical model of the superconducting cavity resonator including the Lorentz force detuning has been developed for a simulation purpose. The digital signal processing is proposed for the field vector detection. The field vector sum control is considered for multiple cavities driven by one klystron. An algebraic, complex domain model is proposed for the system analysis. The c...

  11. Comparison of two superconducting elliptical undulators for generating circularly polarized light

    Directory of Open Access Journals (Sweden)

    C. S. Hwang

    2004-09-01

    Full Text Available The potential use of two planar superconducting elliptical undulators—a vertically wound racetrack coil structure and a staggered array structure—to generate a circularly polarized hard x-ray source was investigated. The magnetic poles and wires of the up and down magnet arrays were rotated in alternating directions on the horizontal plane, an elliptical field is generated to provide circularly polarized light in the electron-storage ring and the energy-recovery linac accelerator. Rapid switching between right- and left-circularly polarized radiations is performed using two undulators with oppositely rotated wires and poles. Given a periodic length of 15 mm and a gap of 5 mm, the magnetic-flux densities in the elliptical undulator are B_{z}=1.2   T (B_{x}=0.6   T and B_{z}=0.35   T (B_{x}=0.15   T in the planar vertically wound racetrack coil and the staggered structure with poles rotated by 35° and 25°, respectively. In maximizing the merit of the flux and the width of the effective field region in the two superconducting elliptical undulators, the trade-off rotation angles of the coils and poles are 20° and 5°, for vertically wound racetrack coil and staggered undulators, respectively.

  12. Theoretical and experimental investigations on synchronization in many-junction arrays of HTSC Josephson junctions. Final report

    International Nuclear Information System (INIS)

    Seidel, P.; Heinz, E.; Pfuch, A.; Machalett, F.; Krech, W.; Basler, M.

    1996-06-01

    Different many-junction arrays of Josephson junctions were studied theoretically to analyse the mechanisms of synchronization, the influence of internal and external parameters and the maximal allowed spread of parameters for the single junctions. Concepts to realize arrays using standard high-T c superconductor technology were created, e.g. the new arrangement of multijunction superconducting loops (MSL). First experimental results show the relevance of this concept. Intrinsic one-dimensional arrays in thin film technology were prepared as mesas out of Bi or Tl 2212 films. to characterize HTSC Josephson junctions methods based on the analysis of microwave-induced steps were developed. (orig.) [de

  13. High-current applications of superconductivity

    International Nuclear Information System (INIS)

    Komarek, P.

    1995-01-01

    The following topics were dealt with: superconducting materials, design principles of superconducting magnets, magnets for research and engineering, superconductivity for power engineering, superconductivity in nuclear fusion technology, economical considerations

  14. Laser activated superconducting switch

    International Nuclear Information System (INIS)

    Wolf, A.A.

    1976-01-01

    A superconducting switch or bistable device is described consisting of a superconductor in a cryogen maintaining a temperature just below the transition temperature, having a window of the proper optical frequency band for passing a laser beam which may impinge on the superconductor when desired. The frequency of the laser is equal to or greater than the optical absorption frequency of the superconducting material and is consistent with the ratio of the gap energy of the switch material to Planck's constant, to cause depairing of electrons, and thereby normalize the superconductor. Some embodiments comprise first and second superconducting metals. Other embodiments feature the two superconducting metals separated by a thin film insulator through which the superconducting electrons tunnel during superconductivity

  15. Microwave kinetic inductance detectors for astronomy and particle detection

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Christian; Monfardini, Alessandro [Institut Neel, CNRS and Universite J. Fourier, Grenoble (France); Roesch, Markus; Schuster, Karl [IRAM, St. Martin d' Heres (France)

    2011-07-01

    A new type of superconducting detector, the Microwave Kinetic Inductance Detector, has recently drawn the attention of the low-temperature detector community. Easy fabrication, high sensitivity, low time constants and most notably the intrinsic capability to frequency multiplexing open new possibilities to applications that need very large array sizes and/or high speed read-out. We develop detector arrays for applications in the domain of astronomy, particle detection, phonon imaging and Helium-physics based on Lumped Element KIDs (LEKIDs). In a LEKID a resonant circuit composed of a discrete inductance and capacitance is coupled to a transmission line. The constant current density in the inductive part makes it a very efficient detector for em-radiation and particles. In this contribution we discuss detector principle, design and measured characteristics. Then we focus on the application for a millimeter wavelength camera, successfully tested at the IRAM 30-meter telescope at Pico Veleta, Spain in October 2010. The current instrument contains two arrays at 100 mK with more than 100 pixels on one read-out-line each for observations at 1.3 and 2 mm. The performances are the best achieved as of today for groundbased KIDs with sensitivities already comparable with existing (horns-coupled bolometers) instruments.

  16. Superconducting linac

    International Nuclear Information System (INIS)

    Bollinger, L.M.; Shepard, K.W.; Wangler, T.P.

    1978-01-01

    This project has two goals: to design, build, and test a small superconducting linac to serve as an energy booster for heavy ions from an FN tandem electrostatic accelerator, and to investigate various aspects of superconducting rf technology. The main design features of the booster are described, a status report on various components (resonators, rf control system, linac control system, cryostats, buncher) is given, and plans for the near future are outlined. Investigations of superconducting-linac technology concern studies on materials and fabrication techniques, resonator diagnostic techniques, rf-phase control, beam dynamics computer programs, asymmetry in accelerating field, and surface-treatment techniques. The overall layout of the to-be-proposed ATLAS, the Argonne Tandem-Linac Accelerator System, is shown; the ATLAS would use superconducting technology to produce beams of 5 to 25 MeV/A. 6 figures

  17. Superconductivity and electron microscopy

    International Nuclear Information System (INIS)

    Hawkes, P.W.; Valdre, U.

    1977-01-01

    In this review article, two aspects of the role of superconductivity in electron microscopy are examined: (i) the development of superconducting devices (mainly lenses) and their incorporation in electron microscopes; (ii) the development of electron microscope techniques for studying fundamental and technological problems associated with superconductivity. The first part opens with a brief account of the relevant properties of conventional lenses, after which the various types of superconducting lenses are described and their properties compared. The relative merits and inconveniences of superconducting and conventional lenses are examined, particular attention being paid to the spherical and chromatic aberration coefficients at accelerating voltages above a megavolt. This part closes with a survey of the various microscope designs that have been built or proposed, incorporating superconducting components. In the second part, some methods that have been or might be used in the study of superconductivity in the electron microscope are described. A brief account of the types of application for which they are suitable is given. (author)

  18. Superconductivity in transition metals.

    Science.gov (United States)

    Slocombe, Daniel R; Kuznetsov, Vladimir L; Grochala, Wojciech; Williams, Robert J P; Edwards, Peter P

    2015-03-13

    A qualitative account of the occurrence and magnitude of superconductivity in the transition metals is presented, with a primary emphasis on elements of the first row. Correlations of the important parameters of the Bardeen-Cooper-Schrieffer theory of superconductivity are highlighted with respect to the number of d-shell electrons per atom of the transition elements. The relation between the systematics of superconductivity in the transition metals and the periodic table high-lights the importance of short-range or chemical bonding on the remarkable natural phenomenon of superconductivity in the chemical elements. A relationship between superconductivity and lattice instability appears naturally as a balance and competition between localized covalent bonding and so-called broken covalency, which favours d-electron delocalization and superconductivity. In this manner, the systematics of superconductivity and various other physical properties of the transition elements are related and unified. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  19. Linear arrangement of metallic and superconducting defects in a thin superconducting sample

    International Nuclear Information System (INIS)

    Barba-Ortega, J.; Sardella, Edson; Albino Aguiar, J.

    2013-01-01

    Highlights: • We study the influence of superconducting and metallic defects on the vortex configurations in a thin mesoscopic disk. • We found that the vortex–defect interaction leads to interesting vortex configurations. • The first vortex entry is always (never) found sitting on the metallic (superconducting) defect position. -- Abstract: The vortex matter in a superconducting disk with a linear configuration of metallic and superconducting defects is studied. Effects associated to the pinning (anti-pinning) force of the metallic (superconducting) defect on the vortex configuration and on the thermodynamic critical fields are analyzed in the framework of the Ginzburg Landau theory. We calculate the loop of the magnetization, vorticity and free energy curves as a function of the magnetic field for a thin disk. Due to vortex–defect attraction for a metallic defect (repulsion for a superconducting defect), the vortices always (never) are found to be sitting on the defect position

  20. Superconducting state mechanisms and properties

    CERN Document Server

    Kresin, Vladimir Z; Wolf, Stuart A

    2014-01-01

    'Superconducting State' provides a very detailed theoretical treatment of the key mechanisms of superconductivity, including the current state of the art (phonons, magnons, and plasmons). A very complete description is given of the electron-phonon mechanism responsible for superconductivity in the majority of superconducting systems, and the history of its development, as well as a detailed description of the key experimental techniques used to study the superconducting state and determine the mechanisms. In addition, there are chapters describing the discovery and properties of the key superconducting compounds that are of the most interest for science, and applications including a special chapter on the cuprate superconductors. It provides detailed treatments of some very novel aspects of superconductivity, including multiple bands (gaps), the "pseudogap" state, novel isotope effects beyond BCS, and induced superconductivity.

  1. Optimization of levitation and guidance forces in a superconducting Maglev system

    Science.gov (United States)

    Yildizer, Irfan; Cansiz, Ahmet; Ozturk, Kemal

    2016-09-01

    Optimization of the levitation for superconducting Maglev systems requires effective use of vertical and guidance forces during the operation. In this respect the levitation and guidance forces in terms of various permanent magnet array configurations are analyzed. The arrangements of permanent magnet arrays interacting with the superconductor are configured for the purpose of increasing the magnetic flux density. According to configurations, modeling the interaction forces between the permanent magnet and the superconductor are established in terms of the frozen image model. The model is complemented with the analytical calculations and provides a reasonable agreement with the experiments. The agreement of the analytical calculation associated with the frozen image model indicates a strong case to establish an optimization, in which provides preliminary analysis before constructing more complex Maglev system.

  2. Enhanced superconductivity of fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Washington, II, Aaron L.; Teprovich, Joseph A.; Zidan, Ragaiy

    2017-06-20

    Methods for enhancing characteristics of superconductive fullerenes and devices incorporating the fullerenes are disclosed. Enhancements can include increase in the critical transition temperature at a constant magnetic field; the existence of a superconducting hysteresis over a changing magnetic field; a decrease in the stabilizing magnetic field required for the onset of superconductivity; and/or an increase in the stability of superconductivity over a large magnetic field. The enhancements can be brought about by transmitting electromagnetic radiation to the superconductive fullerene such that the electromagnetic radiation impinges on the fullerene with an energy that is greater than the band gap of the fullerene.

  3. Superconducting microwave electronics at Lewis Research Center

    Science.gov (United States)

    Warner, Joseph D.; Bhasin, Kul B.; Leonard, Regis F.

    Over the last three years, NASA Lewis Research Center has investigated the application of newly discovered high temperature superconductors to microwave electronics. Using thin films of YBa2Cu3O7-delta and Tl2Ca2Ba2Cu3Ox deposited on a variety of substrates, including strontium titanate, lanthanum gallate, lanthanum aluminate and magnesium oxide, a number of microwave circuits have been fabricated and evaluated. These include a cavity resonator at 60 GHz, microstrip resonators at 35 GHz, a superconducting antenna array at 35 GHz, a dielectric resonator at 9 GHz, and a microstrip filter at 5 GHz. Performance of some of these circuits as well as suggestions for other applications are reported.

  4. Superconducting Microwave Electronics at Lewis Research Center

    Science.gov (United States)

    Warner, Joseph D.; Bhasin, Kul B.; Leonard, Regis F.

    1991-01-01

    Over the last three years, NASA Lewis Research Center has investigated the application of newly discovered high temperature superconductors to microwave electronics. Using thin films of YBa2Cu3O7-delta and Tl2Ca2Ba2Cu3Ox deposited on a variety of substrates, including strontium titanate, lanthanum gallate, lanthanum aluminate and magnesium oxide, a number of microwave circuits have been fabricated and evaluated. These include a cavity resonator at 60 GHz, microstrip resonators at 35 GHz, a superconducting antenna array at 35 GHz, a dielectric resonator at 9 GHz, and a microstrip filter at 5 GHz. Performance of some of these circuits as well as suggestions for other applications are reported.

  5. Hole superconductivity

    International Nuclear Information System (INIS)

    Hirsch, J.E.; Marsiglio, F.

    1989-01-01

    The authors review recent work on a mechanism proposed to explain high T c superconductivity in oxides as well as superconductivity of conventional materials. It is based on pairing of hole carriers through their direct Coulomb interaction, and gives rise to superconductivity because of the momentum dependence of the repulsive interaction in the solid state environment. In the regime of parameters appropriate for high T c oxides this mechanism leads to characteristic signatures that should be experimentally verifiable. In the regime of conventional superconductors most of these signatures become unobservable, but the characteristic dependence of T c on band filling survives. New features discussed her include the demonstration that superconductivity can result from repulsive interactions even if the gap function does not change sign and the inclusion of a self-energy correction to the hole propagator that reduces the range of band filling where T c is not zero

  6. Superconducting Fullerene Nanowhiskers

    Directory of Open Access Journals (Sweden)

    Yoshihiko Takano

    2012-04-01

    Full Text Available We synthesized superconducting fullerene nanowhiskers (C60NWs by potassium (K intercalation. They showed large superconducting volume fractions, as high as 80%. The superconducting transition temperature at 17 K was independent of the K content (x in the range between 1.6 and 6.0 in K-doped C60 nanowhiskers (KxC60NWs, while the superconducting volume fractions changed with x. The highest shielding fraction of a full shielding volume was observed in the material of K3.3C60NW by heating at 200 °C. On the other hand, that of a K-doped fullerene (K-C60 crystal was less than 1%. We report the superconducting behaviors of our newly synthesized KxC60NWs in comparison to those of KxC60 crystals, which show superconductivity at 19 K in K3C60. The lattice structures are also discussed, based on the x-ray diffraction (XRD analyses.

  7. Design considerations for large detector arrays on submillimeter-wave telescopes

    Science.gov (United States)

    Stark, Antony A.

    2000-07-01

    The emerging technology of large (approximately 10,000 pixel) submillimeter-wave bolometer arrays presents a novel optical design problem -- how can such arrays be fed by diffraction- limited telescope optics where the primary mirror is less than 100,000 wavelengths in diameter? Standard Cassegrain designs for radiotelescope optics exhibit focal surface curvature so large that detectors cannot be placed more than 25 beam diameters from the central ray. The problem is worse for Ritchey-Chretien designs, because these minimize coma while increasing field curvature. Classical aberrations, including coma, are usually dominated by diffraction in submillimeter- wave single dish telescopes. The telescope designer must consider (1) diffraction, (2) aberration, (3) curvature of field, (4) cross-polarization, (5) internal reflections, (6) the effect of blockages, (7) means of beam chopping on- and off-source, (8) gravitational and thermal deformations of the primary mirror, (9) the physical mounting of large detector packages, and (10) the effect of gravity and (11) vibration on those detectors. Simultaneous optimization of these considerations in the case of large detector arrays leads to telescopes that differ considerably from standard radiotelescope designs. Offset optics provide flexibility for mounting detectors, while eliminating blockage and internal reflections. Aberrations and cross-polarization can be the same as on-axis designs having the same diameter and focal length. Trade-offs include the complication of primary mirror homology and an increase in overall cost. A dramatic increase in usable field of view can be achieved using shaped optics. Solutions having one to six mirrors will be discussed, including possible six-mirror design for the proposed South Pole 10 m telescope.

  8. Preliminary design of a tangentially viewing imaging bolometer for NSTX-U

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, B. J., E-mail: peterson@LHD.nifs.ac.jp; Mukai, K. [National Institute for Fusion Science, Toki 509-5292 (Japan); SOKENDAI (The Graduate University for Advance Studies), Toki 509-5292 (Japan); Sano, R. [National Institutes for Quantum and Radiological Science and Technology, Naka, Ibaraki 311-0193 (Japan); Reinke, M. L.; Canik, J. M.; Lore, J. D.; Gray, T. K. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Delgado-Aparicio, L. F.; Jaworski, M. A. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Eden, G. G. van [FOM Institute DIFFER, 5612 AJ Eindhoven (Netherlands)

    2016-11-15

    The infrared imaging video bolometer (IRVB) measures plasma radiated power images using a thin metal foil. Two different designs with a tangential view of NSTX-U are made assuming a 640 × 480 (1280 × 1024) pixel, 30 (105) fps, 50 (20) mK, IR camera imaging the 9 cm × 9 cm × 2 μm Pt foil. The foil is divided into 40 × 40 (64 × 64) IRVB channels. This gives a spatial resolution of 3.4 (2.2) cm on the machine mid-plane. The noise equivalent power density of the IRVB is given as 113 (46) μW/cm{sup 2} for a time resolution of 33 (20) ms. Synthetic images derived from Scrape Off Layer Plasma Simulation data using the IRVB geometry show peak signal levels ranging from ∼0.8 to ∼80 (∼0.36 to ∼26) mW/cm{sup 2}.

  9. Superconducting quantum electronics

    International Nuclear Information System (INIS)

    Kose, V.

    1989-01-01

    This book reviews recent accomplishments, presents new results and discusses possible future developments of superconducting quantum electronics and high T c superconductivity. The three main parts of the book deal with fundamentals, sensitive detectors, and precision metrology. New results reported include: correct equivalent circuits modelling superconducting electronic devices; exact solution of the Mattis-Bardeen equations describing various experiments for thin films; complete theoretical description and experimental results for a new broad band spectrum analyzer; a new Josephson junction potentiometer allowing tracing of unknown voltage ratios back to well-known frequency ratios; and fast superconducting SQUID shift registers enabling the production of calculable noise power spectra in the microwave region

  10. Transverse ratchet effect and superconducting vortices: simulation and experiment

    International Nuclear Information System (INIS)

    Dinis, L; Parrondo, J M R; Perez de Lara, D; Gonzalez, E M; Vicent, J L; Anguita, J V

    2009-01-01

    A transverse ratchet effect has been measured in magnetic/superconducting hybrid films fabricated by electron beam lithography and magnetron sputtering techniques. The samples are Nb films grown on top of an array of Ni nanotriangles. Injecting an ac current parallel to the triangle reflection symmetry axis yields an output dc voltage perpendicular to the current, due to a net motion of flux vortices in the superconductor. The effect is reproduced by numerical simulations of vortices as Langevin particles with realistic parameters. Simulations provide an intuitive picture of the ratchet mechanism, revealing the fundamental role played by the random intrinsic pinning of the superconductor.

  11. Initial operation of the Argonne superconducting heavy-ion linac

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K. W.

    1979-01-01

    Initial operation and recent development of the Argonne superconducting heavy-ion linac are discussed. The linac has been developed in order to demonstrate a cost-effective means of extending the performance of electrostatic tandem accelerators. The results of beam acceleration tests which began in June 1978 are described. At present 7 of a planned array of 22 resonators are operating on-line, and the linac system provides an effective accelerating potential of 7.5 MV. Although some technical problems remain, the level of performance and reliability is sufficient that appreciable beam time is becoming available to users.

  12. Superconductivity in graphite intercalation compounds

    International Nuclear Information System (INIS)

    Smith, Robert P.; Weller, Thomas E.; Howard, Christopher A.; Dean, Mark P.M.; Rahnejat, Kaveh C.; Saxena, Siddharth S.; Ellerby, Mark

    2015-01-01

    Highlights: • Historical background of graphite intercalates. • Superconductivity in graphite intercalates and its place in the field of superconductivity. • Recent developments. • Relevant modeling of superconductivity in graphite intercalates. • Interpretations that pertain and questions that remain. - Abstract: The field of superconductivity in the class of materials known as graphite intercalation compounds has a history dating back to the 1960s (Dresselhaus and Dresselhaus, 1981; Enoki et al., 2003). This paper recontextualizes the field in light of the discovery of superconductivity in CaC 6 and YbC 6 in 2005. In what follows, we outline the crystal structure and electronic structure of these and related compounds. We go on to experiments addressing the superconducting energy gap, lattice dynamics, pressure dependence, and how these relate to theoretical studies. The bulk of the evidence strongly supports a BCS superconducting state. However, important questions remain regarding which electronic states and phonon modes are most important for superconductivity, and whether current theoretical techniques can fully describe the dependence of the superconducting transition temperature on pressure and chemical composition

  13. Superconductivity in graphite intercalation compounds

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Robert P. [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Weller, Thomas E.; Howard, Christopher A. [Department of Physics & Astronomy, University College of London, Gower Street, London WCIE 6BT (United Kingdom); Dean, Mark P.M. [Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY 11973 (United States); Rahnejat, Kaveh C. [Department of Physics & Astronomy, University College of London, Gower Street, London WCIE 6BT (United Kingdom); Saxena, Siddharth S. [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Ellerby, Mark, E-mail: mark.ellerby@ucl.ac.uk [Department of Physics & Astronomy, University College of London, Gower Street, London WCIE 6BT (United Kingdom)

    2015-07-15

    Highlights: • Historical background of graphite intercalates. • Superconductivity in graphite intercalates and its place in the field of superconductivity. • Recent developments. • Relevant modeling of superconductivity in graphite intercalates. • Interpretations that pertain and questions that remain. - Abstract: The field of superconductivity in the class of materials known as graphite intercalation compounds has a history dating back to the 1960s (Dresselhaus and Dresselhaus, 1981; Enoki et al., 2003). This paper recontextualizes the field in light of the discovery of superconductivity in CaC{sub 6} and YbC{sub 6} in 2005. In what follows, we outline the crystal structure and electronic structure of these and related compounds. We go on to experiments addressing the superconducting energy gap, lattice dynamics, pressure dependence, and how these relate to theoretical studies. The bulk of the evidence strongly supports a BCS superconducting state. However, important questions remain regarding which electronic states and phonon modes are most important for superconductivity, and whether current theoretical techniques can fully describe the dependence of the superconducting transition temperature on pressure and chemical composition.

  14. Experimental and Computational Studies of the Superconducting Phase Transition of Quasi 1D Superconductors

    Science.gov (United States)

    Wong, Chi Ho

    In this PhD project, the feasibility of establishing a state with vanishing resistance in quasi-1D superconductors are studied. In the first stage, extrinsic quasi-1D superconductors based on composite materials made by metallic nanowire arrays embedded in mesoporous silica substrates, such as Pb-SBA-15 and NbN-SBA-15 (fabricated by a Chemical Vapor Deposition technique) are investigated. Two impressive outcomes in Pb-SBA-15 are found, including an enormous enhancement of the upper critical field from 0.08T to 14T and an increase of the superconducting transition temperature onset s from 7.2 to 11K. The second stage is to apply Monte Carlo simulations to model the quasi-1D superconductor, considering its penetration depth, coherence length, defects, electron mean free path, tunneling barrier and insulating width between the nanowires. The Monte Carlo results provide a clear picture to approach to stage 3, which represents a study of the intrinsic quasi-1D superconductor Sc3CoC4, which contains parallel arrays of 1D superconducting CoC4 ribbons with weak transverse Josephson or Proximity interaction, embedded in a Sc matrix. According to our previous work, a BKT transition in the lateral plane is believed to be the physics behind the vanishing resistance of quasi-1D superconductors, because it activates a dimensional crossover from a 1D fluctuating superconductivity at high temperature to a 3D bulk phase coherent state in the entire material at low temperatures. Moreover, we decided to study thin 1D Sn nanowires without substrate, which display very similar superconducting properties to Pb-SBA-15 with a strong critical field and Tc enhancement. Finally, a preliminary research on a novel quasi-2D superconductor formed by parallel 2D mercury sheets that are separated by organic molecules is presented. The latter material may represent a model system to study the effect of a layered structure, which is believed to be an effective ingredient to design high temperature

  15. Modern high-temperature superconductivity

    International Nuclear Information System (INIS)

    Ching Wu Chu

    1988-01-01

    Ever since the discovery of superconductivity in 1911, its unusual scientific challenge and great technological potential have been recognized. For the past three-quarters of a century, superconductivity has done well on the science front. This is because sueprconductivity is interesting not only just in its own right but also in its ability to act as a probe to many exciting nonsuperconducting phenomena. For instance, it has continued to provide bases for vigorous activities in condensed matter science. Among the more recent examples are heavy-fermion systems and organic superconductors. During this same period of time, superconductivity has also performed admirably in the applied area. Many ideas have been conceived and tested, making use of the unique characteristics of superconductivity - zero resistivity, quantum interference phenomena, and the Meissner effect. In fact, it was not until late January 1987 that it became possible to achieve superconductivity with the mere use of liquid nitrogen - which is plentiful, cheap, efficient, and easy to handle - following the discovery of supercondictivity above 90 K in Y-Ba-Cu-O, the first genuine quaternary superconductor. Superconductivity above 90 K poses scientific and technological challenges not previously encountered: no existing theories can adequately describe superconductivity above 40 K and no known techniques can economically process the materials for full-scale applications. In this paper, therefore, the author recalls a few events leading to the discovery of the new class of quaternary compounds with a superconducting transition temperature T c in the 90 K range, describes the current experimental status of high-temperature superconductivity and, finally, discusses the prospect of very-high-temperature superconductivity, i.e., with a T c substantially higher than 100 K. 97 refs., 7 figs

  16. Inhomogeneous superconductivity in a ferromagnet

    International Nuclear Information System (INIS)

    Kontos, T.; Aprili, M.; Lesueur, J.; Genet, F.; Boursier, R.; Grison, X.

    2003-01-01

    We have studied a new superconducting state where the condensate wave function resulting from conventional pairing, is modified by an exchange field. Superconductivity is induced into a ferromagnetic thin film (F) by the proximity effect with a superconducting reservoir (S). We observed oscillations of the superconducting order parameter induced in F as a function of the distance from the S/F interface. They originate from the finite momentum transfer provided to Cooper pairs by the splitting of the spin up and down bands. We measured the superconducting density of states in F by tunneling spectroscopy and the Josephson critical current when F is coupled with a superconducting counter-electrode. Negative values of the superconducting order parameter are revealed by capsized tunneling spectra in F and a negative Josephson coupling (π-junction)

  17. Superconducting materials for large scale applications

    Energy Technology Data Exchange (ETDEWEB)

    Scanlan, Ronald M.; Malozemoff, Alexis P.; Larbalestier, David C.

    2004-05-06

    Significant improvements in the properties ofsuperconducting materials have occurred recently. These improvements arebeing incorporated into the latest generation of wires, cables, and tapesthat are being used in a broad range of prototype devices. These devicesinclude new, high field accelerator and NMR magnets, magnets for fusionpower experiments, motors, generators, and power transmission lines.These prototype magnets are joining a wide array of existing applicationsthat utilize the unique capabilities of superconducting magnets:accelerators such as the Large Hadron Collider, fusion experiments suchas ITER, 930 MHz NMR, and 4 Tesla MRI. In addition, promising newmaterials such as MgB2 have been discovered and are being studied inorder to assess their potential for new applications. In this paper, wewill review the key developments that are leading to these newapplications for superconducting materials. In some cases, the key factoris improved understanding or development of materials with significantlyimproved properties. An example of the former is the development of Nb3Snfor use in high field magnets for accelerators. In other cases, thedevelopment is being driven by the application. The aggressive effort todevelop HTS tapes is being driven primarily by the need for materialsthat can operate at temperatures of 50 K and higher. The implications ofthese two drivers for further developments will be discussed. Finally, wewill discuss the areas where further improvements are needed in order fornew applications to be realized.

  18. WORKSHOP: Radiofrequency superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1984-10-15

    The Second Workshop on Radiofrequency Superconductivity was held at CERN from 23-27 July, four years after the first, organized at Karlsruhe. 35 invited talks were presented to the about 80 participants from Australia, Brazil, Europe, Japan and the United States. For the first time, ten Laboratories operating or planning superconducting accelerators for heavy ions participated and shared their experience with the community proposing the use of superconducting accelerating sections for electron accelerators.

  19. WORKSHOP: Radiofrequency superconductivity

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    The Second Workshop on Radiofrequency Superconductivity was held at CERN from 23-27 July, four years after the first, organized at Karlsruhe. 35 invited talks were presented to the about 80 participants from Australia, Brazil, Europe, Japan and the United States. For the first time, ten Laboratories operating or planning superconducting accelerators for heavy ions participated and shared their experience with the community proposing the use of superconducting accelerating sections for electron accelerators

  20. Process for producing clad superconductive materials

    International Nuclear Information System (INIS)

    Cass, R.B.; Ott, K.C.; Peterson, D.E.

    1992-01-01

    This patent describes a process for fabricating superconducting composite wire. It comprises placing a superconductive precursor admixture capable of undergoing self propagating combustion in stoichiometric amounts sufficient to form a superconductive product within an oxygen-porous metal tube; sealing one end of the tube; igniting the superconductive precursor admixture whereby the superconductive precursor admixture endburns along the length of the admixture; and cross-section reducing the tube at a rate substantially equal to the rate of burning of the superconductive precursor admixture and at a point substantially planar with the burnfront of the superconductive precursor mixture, whereby a clad superconductive product is formed in situ

  1. Organic superconductivity

    International Nuclear Information System (INIS)

    Jerome, D.

    1980-01-01

    We present the experimental evidences for the existence of a superconducting state in the Quasi One Dimensional organic conductor (TMTSF) 2 PF 6 . Superconductivity occuring at 1 K under 12 kbar is characterized by a zero resistance diamagnetic state. The anistropy of the upper critical field of this type II superconductor is consistent with the band structure anistropy. We present evidences for the existence of large superconducting precursor effects giving rise to a dominant paraconductive contribution below 40 K. We also discuss the anomalously large pressure dependence of T sb(s), which drops to 0.19 K under 24 kbar in terms of the current theories. (author)

  2. Enhancing the utilization of photovoltaic power generation by superconductive magnetic energy storage

    International Nuclear Information System (INIS)

    Tam, K.S.; Kumar, P.; Foreman, M.

    1989-01-01

    This paper demonstrates that a superconductive magnetic energy storage (SMES) system can enhance large scale utilization of PV generation. With SMES support, power generated from PV arrays van be fully utilized under different weather conditions and PV penetrations can be increased to significant levels without causing adverse effects to the power system. Coupled with PV generation, a SMES system is even more effective in performing diurnal load leveling. A coordinated PV/SMES operation scheme is proposed and demonstrated under different weather conditions

  3. Pt silicide/poly-Si Schottky diodes as temperature sensors for bolometers

    Energy Technology Data Exchange (ETDEWEB)

    Yuryev, V. A., E-mail: vyuryev@kapella.gpi.ru; Chizh, K. V.; Chapnin, V. A.; Mironov, S. A.; Dubkov, V. P.; Uvarov, O. V.; Kalinushkin, V. P. [A. M. Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilov Street, Moscow 119991 (Russian Federation); Senkov, V. M. [P. N. Lebedev Physical Institute of the Russian Academy of Sciences, 53 Leninskiy Avenue, Moscow 119991 (Russian Federation); Nalivaiko, O. Y. [JSC “Integral” – “Integral” Holding Management Company, 121A, Kazintsa I. P. Street, Minsk 220108 (Belarus); Novikau, A. G.; Gaiduk, P. I. [Belarusian State University, 4 Nezavisimosti Avenue, 220030 Minsk (Belarus)

    2015-05-28

    Platinum silicide Schottky diodes formed on films of polycrystalline Si doped by phosphorus are demonstrated to be efficient and manufacturable CMOS-compatible temperature sensors for microbolometer detectors of radiation. Thin-film platinum silicide/poly-Si diodes have been produced by a CMOS-compatible process on artificial Si{sub 3}N{sub 4}/SiO{sub 2}/Si(001) substrates simulating the bolometer cells. Layer structure and phase composition of the original Pt/poly-Si films and the Pt silicide/poly-Si films synthesized by a low-temperature process have been studied by means of the scanning transmission electron microscopy; they have also been explored by means of the two-wavelength X-ray structural phase analysis and the X-ray photoelectron spectroscopy. Temperature coefficient of voltage for the forward current of a single diode is shown to reach the value of about −2%/ °C in the temperature interval from 25 to 50 °C.

  4. Superconducting Wind Turbine Generators

    Directory of Open Access Journals (Sweden)

    Yunying Pan

    2016-08-01

    Full Text Available Wind energy is well known as a renewable energy because its clean and less polluted characteristic, which is the foundation of development modern wind electricity. To find more efficient wind turbine is the focus of scientists around the world. Compared from conventional wind turbines, superconducting wind turbine generators have advantages at zero resistance, smaller size and lighter weight. Superconducting wind turbine will inevitably become the main trends in this area. This paper intends to introduce the basic concept and principle of superconductivity, and compare form traditional wind turbine to obtain superiority, then to summary three proposed machine concept.While superconductivity have difficulty  in modern technology and we also have proposed some challenges in achieving superconducting wind turbine finally.

  5. Superconducting cermets

    International Nuclear Information System (INIS)

    Goyal, A.; Funkenbusch, P.D.; Chang, G.C.S.; Burns, S.J.

    1988-01-01

    Two distant classes of superconducting cermets can be distinguished, depending on whether or not a fully superconducting skeleton is established. Both types of cermets have been successfully fabricated using non-noble metals, with as high as 60wt% of the metal phase. The electrical, magnetic and mechanical behavior of these composites is discussed

  6. Rf superconducting devices

    International Nuclear Information System (INIS)

    Hartwig, W.H.; Passow, C.

    1975-01-01

    Topics discussed include (1) the theory of superconductors in high-frequency fields (London surface impedance, anomalous normal surface resistance, pippard nonlocal theory, quantum mechanical model, superconductor parameters, quantum mechanical calculation techniques for the surface, impedance, and experimental verification of surface impedance theories); (2) residual resistance (separation of losses, magnetic field effects, surface resistance of imperfect and impure conductors, residual loss due to acoustic coupling, losses from nonideal surfaces, high magnetic field losses, field emission, and nonlinear effects); (3) design and performance of superconducting devices (design considerations, materials and fabrication techniques, measurement of performance, and frequency stability); (4) devices for particle acceleration and deflection (advantages and problems of using superconductors, accelerators for fast particles, accelerators for particles with slow velocities, beam optical devices separators, and applications and projects under way); (5) applications of low-power superconducting resonators (superconducting filters and tuners, oscillators and detectors, mixers and amplifiers, antennas and output tanks, superconducting resonators for materials research, and radiation detection with loaded superconducting resonators); and (6) transmission and delay lines

  7. Superconducting Ferromagnetic Nanodiamond.

    Science.gov (United States)

    Zhang, Gufei; Samuely, Tomas; Xu, Zheng; Jochum, Johanna K; Volodin, Alexander; Zhou, Shengqiang; May, Paul W; Onufriienko, Oleksandr; Kačmarčík, Jozef; Steele, Julian A; Li, Jun; Vanacken, Johan; Vacík, Jiri; Szabó, Pavol; Yuan, Haifeng; Roeffaers, Maarten B J; Cerbu, Dorin; Samuely, Peter; Hofkens, Johan; Moshchalkov, Victor V

    2017-06-27

    Superconductivity and ferromagnetism are two mutually antagonistic states in condensed matter. Research on the interplay between these two competing orderings sheds light not only on the cause of various quantum phenomena in strongly correlated systems but also on the general mechanism of superconductivity. Here we report on the observation of the electronic entanglement between superconducting and ferromagnetic states in hydrogenated boron-doped nanodiamond films, which have a superconducting transition temperature T c ∼ 3 K and a Curie temperature T Curie > 400 K. In spite of the high T Curie , our nanodiamond films demonstrate a decrease in the temperature dependence of magnetization below 100 K, in correspondence to an increase in the temperature dependence of resistivity. These anomalous magnetic and electrical transport properties reveal the presence of an intriguing precursor phase, in which spin fluctuations intervene as a result of the interplay between the two antagonistic states. Furthermore, the observations of high-temperature ferromagnetism, giant positive magnetoresistance, and anomalous Hall effect bring attention to the potential applications of our superconducting ferromagnetic nanodiamond films in magnetoelectronics, spintronics, and magnetic field sensing.

  8. Microfabricated optically pumped magnetometer arrays for biomedical imaging

    Science.gov (United States)

    Perry, A. R.; Sheng, D.; Krzyzewski, S. P.; Geller, S.; Knappe, S.

    2017-02-01

    Optically-pumped magnetometers have demonstrated magnetic field measurements as precise as the best superconducting quantum interference device magnetometers. Our group develops miniature alkali atom-based magnetic sensors using microfabrication technology. Our sensors do not require cryogenic cooling, and can be positioned very close to the sample, making these sensors an attractive option for development in the medical community. We will present our latest chip-scale optically-pumped gradiometer developed for array applications to image magnetic fields from the brain noninvasively. These developments should lead to improved spatial resolution, and potentially sensitive measurements in unshielded environments.

  9. Advanced ACTPol Cryogenic Detector Arrays and Readout

    Science.gov (United States)

    Henderson, S. W.; Allison, R.; Austermann, J.; Baildon, T.; Battaglia, N.; Beall, J. A.; Becker, D.; De Bernardis, F.; Bond, J. R.; Calabrese, E.; Choi, S. K.; Coughlin, K. P.; Crowley, K. T.; Datta, R.; Devlin, M. J.; Duff, S. M.; Dunkley, J.; Dünner, R.; van Engelen, A.; Gallardo, P. A.; Grace, E.; Hasselfield, M.; Hills, F.; Hilton, G. C.; Hincks, A. D.; Hloẑek, R.; Ho, S. P.; Hubmayr, J.; Huffenberger, K.; Hughes, J. P.; Irwin, K. D.; Koopman, B. J.; Kosowsky, A. B.; Li, D.; McMahon, J.; Munson, C.; Nati, F.; Newburgh, L.; Niemack, M. D.; Niraula, P.; Page, L. A.; Pappas, C. G.; Salatino, M.; Schillaci, A.; Schmitt, B. L.; Sehgal, N.; Sherwin, B. D.; Sievers, J. L.; Simon, S. M.; Spergel, D. N.; Staggs, S. T.; Stevens, J. R.; Thornton, R.; Van Lanen, J.; Vavagiakis, E. M.; Ward, J. T.; Wollack, E. J.

    2016-08-01

    Advanced ACTPol is a polarization-sensitive upgrade for the 6 m aperture Atacama Cosmology Telescope, adding new frequencies and increasing sensitivity over the previous ACTPol receiver. In 2016, Advanced ACTPol will begin to map approximately half the sky in five frequency bands (28-230 GHz). Its maps of primary and secondary cosmic microwave background anisotropies—imaged in intensity and polarization at few arcminute-scale resolution—will enable precision cosmological constraints and also a wide array of cross-correlation science that probes the expansion history of the universe and the growth of structure via gravitational collapse. To accomplish these scientific goals, the Advanced ACTPol receiver will be a significant upgrade to the ACTPol receiver, including four new multichroic arrays of cryogenic, feedhorn-coupled AlMn transition edge sensor polarimeters (fabricated on 150 mm diameter wafers); a system of continuously rotating meta-material silicon half-wave plates; and a new multiplexing readout architecture which uses superconducting quantum interference devices and time division to achieve a 64-row multiplexing factor. Here we present the status and scientific goals of the Advanced ACTPol instrument, emphasizing the design and implementation of the Advanced ACTPol cryogenic detector arrays.

  10. Superconductivity and its application

    International Nuclear Information System (INIS)

    Spadoni, M.

    1988-01-01

    This paper, after a short introduction to superconductivity and to multifilamentary superconducting composites is aiming to review the state of the art and the future perspective of some of the applications of the superconducting materials. The main interest is focussed to large scale applications like, for istance, magnets for accelerators or fusion reactors, superconducting system for NMR thomography, etc. A short paragraph is dedicated to applications for high sensitivity instrumentation. The paper is then concluded by some considerations about the potentialities of the newly discovered high critical temperature materials

  11. WORKSHOPS: Radiofrequency superconductivity

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    In the continual push towards higher energy particle beams, superconducting radiofrequency techniques now play a vital role, highlighted in the fifth workshop on radiofrequency superconductivity, held at DESY from 19 - 24 August 1991

  12. WORKSHOPS: Radiofrequency superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1992-01-15

    In the continual push towards higher energy particle beams, superconducting radiofrequency techniques now play a vital role, highlighted in the fifth workshop on radiofrequency superconductivity, held at DESY from 19 - 24 August 1991.

  13. 'Speedy' superconducting circuits

    International Nuclear Information System (INIS)

    Holst, T.

    1994-01-01

    The most promising concept for realizing ultra-fast superconducting digital circuits is the Rapid Single Flux Quantum (RSFQ) logic. The basic physical principle behind RSFQ logic, which include the storage and transfer of individual magnetic flux quanta in Superconducting Quantum Interference Devices (SQUIDs), is explained. A Set-Reset flip-flop is used as an example of the implementation of an RSFQ based circuit. Finally, the outlook for high-temperature superconducting materials in connection with RSFQ circuits is discussed in some details. (au)

  14. Superconductivity

    International Nuclear Information System (INIS)

    Buller, L.; Carrillo, F.; Dietert, R.; Kotziapashis, A.

    1989-01-01

    Superconductors are materials which combine the property of zero electric resistance with the capability to exclude any adjacent magnetic field. This leads to many large scale applications such as the much publicized levitating train, generation of magnetic fields in MHD electric generators, and special medical diagnostic equipment. On a smaller-scale, superconductive materials could replace existing resistive connectors and decrease signal delays by reducing the RLC time constants. Thus, a computer could operate at much higher speeds, and consequently at lower power levels which would reduce the need for heat removal and allow closer spacing of circuitry. Although technical advances and proposed applications are constantly being published, it should be recognized that superconductivity is a slowly developing technology. It has taken scientists almost eighty years to learn what they now know about this material and its function. The present paper provides an overview of the historical development of superconductivity and describes some of the potential applications for this new technology as it pertains to the electronics industry

  15. Development of superconducting magnetic bearing using superconducting coil and bulk superconductor

    Energy Technology Data Exchange (ETDEWEB)

    Seino, H; Nagashima, K; Arai, Y [Railway Technical Research Institute, Hikari-cho 2-8-38, Kokubunji-shi, Tokyo (Japan)], E-mail: seino@rtri.or.jp

    2008-02-01

    The authors conducted a study on superconducting magnetic bearing, which consists of superconducting rotor and stator to apply the flywheel energy-storage system for railways. In this study, high temperature bulk superconductor (HTS bulk) was combined with superconducting coils to increase the load capacity of the bearing. In the first step of the study, the thrust rolling bearing was selected for application by using liquid nitrogen cooled HTS bulk. 60mm-diameter HTS bulks and superconducting coil which generated a high gradient of magnetic field by cusp field were adopted as a rotor and a stator for superconducting magnetic bearing, respectively. The results of the static load test and the rotation test, creep of the electromagnetic forces caused by static flux penetration and AC loss due to eccentric rotation were decreased to the level without any problems in substantial use by using two HTS bulks. In the result of verification of static load capacity, levitation force (thrust load) of 8900N or more was supportable, and stable static load capacity was obtainable when weight of 460kg was levitated.

  16. Development of superconducting magnetic bearing using superconducting coil and bulk superconductor

    International Nuclear Information System (INIS)

    Seino, H; Nagashima, K; Arai, Y

    2008-01-01

    The authors conducted a study on superconducting magnetic bearing, which consists of superconducting rotor and stator to apply the flywheel energy-storage system for railways. In this study, high temperature bulk superconductor (HTS bulk) was combined with superconducting coils to increase the load capacity of the bearing. In the first step of the study, the thrust rolling bearing was selected for application by using liquid nitrogen cooled HTS bulk. 60mm-diameter HTS bulks and superconducting coil which generated a high gradient of magnetic field by cusp field were adopted as a rotor and a stator for superconducting magnetic bearing, respectively. The results of the static load test and the rotation test, creep of the electromagnetic forces caused by static flux penetration and AC loss due to eccentric rotation were decreased to the level without any problems in substantial use by using two HTS bulks. In the result of verification of static load capacity, levitation force (thrust load) of 8900N or more was supportable, and stable static load capacity was obtainable when weight of 460kg was levitated

  17. Superconductivity basics and applications to magnets

    CERN Document Server

    Sharma, R G

    2015-01-01

    This book presents the basics and applications of superconducting magnets. It explains the phenomenon of superconductivity, theories of superconductivity, type II superconductors and high-temperature cuprate superconductors. The main focus of the book is on the application to superconducting magnets to accelerators and fusion reactors and other applications of superconducting magnets. The thermal and electromagnetic stability criteria of the conductors and the present status of the fabrication techniques for future magnet applications are addressed. The book is based on the long experience of the author in studying superconducting materials, building magnets and numerous lectures delivered to scholars. A researcher and graduate student will enjoy reading the book to learn various aspects of magnet applications of superconductivity. The book provides the knowledge in the field of applied superconductivity in a comprehensive way.

  18. The Atacama Cosmology Telescope: The Receiver and Instrumentation

    Science.gov (United States)

    Swetz, D. S.; Ade, P. A. R.; Amiri, M.; Appel, J. W.; Burger, B.; Devlin, M. J.; Dicker, S. R.; Doriese, W. B.; Essinger-Hileman, T.; Fisher, R. P.; hide

    2010-01-01

    The Atacama Cosmology Telescope was designed to measure small-scale anisotropies in the Cosmic Microwave Background and detect galaxy clusters through the Sunyaev-Zel'dovich effect. The instrument is located on Cerro Taco in the Atacama Desert, at an altitude of 5190 meters. A six-met.er off-axis Gregorian telescope feeds a new type of cryogenic receiver, the Millimeter Bolometer Array Camera. The receiver features three WOO-element arrays of transition-edge sensor bolometers for observations at 148 GHz, 218 GHz, and 277 GHz. Each detector array is fed by free space mm-wave optics. Each frequency band has a field of view of approximately 22' x 26'. The telescope was commissioned in 2007 and has completed its third year of operations. We discuss the major components of the telescope, camera, and related systems, and summarize the instrument performance.

  19. OVERVIEW OF THE ATACAMA COSMOLOGY TELESCOPE: RECEIVER, INSTRUMENTATION, AND TELESCOPE SYSTEMS

    International Nuclear Information System (INIS)

    Swetz, D. S.; Devlin, M. J.; Dicker, S. R.; Ade, P. A. R.; Amiri, M.; Battistelli, E. S.; Burger, B.; Halpern, M.; Hasselfield, M.; Appel, J. W.; Essinger-Hileman, T.; Fisher, R. P.; Fowler, J. W.; Hincks, A. D.; Jarosik, N.; Chervenak, J.; Doriese, W. B.; Hilton, G. C.; Irwin, K. D.; Duenner, R.

    2011-01-01

    The Atacama Cosmology Telescope was designed to measure small-scale anisotropies in the cosmic microwave background and detect galaxy clusters through the Sunyaev-Zel'dovich effect. The instrument is located on Cerro Toco in the Atacama Desert, at an altitude of 5190 m. A 6 m off-axis Gregorian telescope feeds a new type of cryogenic receiver, the Millimeter Bolometer Array Camera. The receiver features three 1000-element arrays of transition-edge sensor bolometers for observations at 148 GHz, 218 GHz, and 277 GHz. Each detector array is fed by free space millimeter-wave optics. Each frequency band has a field of view of approximately 22' x 26'. The telescope was commissioned in 2007 and has completed its third year of operations. We discuss the major components of the telescope, camera, and related systems, and summarize the instrument performance.

  20. Overview of the Atacama Cosmology Telescope: Receiver, Instrumentation, and Telescope Systems

    Science.gov (United States)

    Swetz, D. S.; Ade, P. A. R.; Amiri, M.; Appel, J. W.; Battistelli, E. S.; Burger, B.; Chervenak, J.; Devlin, M. J.; Dicker, S. R.; Doriese, W. B.; Dünner, R.; Essinger-Hileman, T.; Fisher, R. P.; Fowler, J. W.; Halpern, M.; Hasselfield, M.; Hilton, G. C.; Hincks, A. D.; Irwin, K. D.; Jarosik, N.; Kaul, M.; Klein, J.; Lau, J. M.; Limon, M.; Marriage, T. A.; Marsden, D.; Martocci, K.; Mauskopf, P.; Moseley, H.; Netterfield, C. B.; Niemack, M. D.; Nolta, M. R.; Page, L. A.; Parker, L.; Staggs, S. T.; Stryzak, O.; Switzer, E. R.; Thornton, R.; Tucker, C.; Wollack, E.; Zhao, Y.

    2011-06-01

    The Atacama Cosmology Telescope was designed to measure small-scale anisotropies in the cosmic microwave background and detect galaxy clusters through the Sunyaev-Zel'dovich effect. The instrument is located on Cerro Toco in the Atacama Desert, at an altitude of 5190 m. A 6 m off-axis Gregorian telescope feeds a new type of cryogenic receiver, the Millimeter Bolometer Array Camera. The receiver features three 1000-element arrays of transition-edge sensor bolometers for observations at 148 GHz, 218 GHz, and 277 GHz. Each detector array is fed by free space millimeter-wave optics. Each frequency band has a field of view of approximately 22' × 26'. The telescope was commissioned in 2007 and has completed its third year of operations. We discuss the major components of the telescope, camera, and related systems, and summarize the instrument performance.

  1. Superconductivity application technologies. Superconducting quadrupole magnet and cooling system for KEK B factory

    International Nuclear Information System (INIS)

    Tsuchiya, Kiyosumi; Yamaguchi, Kiyoshi; Sakurabata, Hiroaki; Seido, Masahiro; Matsumoto, Kozo.

    1997-01-01

    At present in National Laboratory for High Energy Physics (KEK), the construction of B factory is in progress. By colliding 8 GeV electrons and 3.5 GeV positrons, this facility generates large amounts of B mesons and anti-B mesons, and performs the elementary particle experiment of high accuracy. It is the collision type accelerator of asymmetric two-ring type comprising 8 GeV and 3.5 GeV rings. In the field of high energy physics, superconductivity technology has been put to practical use. As the objects of superconductivity technology, there are dipole magnet for bending beam, quadrupole magnet for adjusting beam, large solenoid magnet used for detector and so on. Superconducting magnets which are indispensable for high energy, superconducting wire material suitable to accelerators, and the liquid helium cooling system for maintaining superconducting magnets at 4.4 K are reported. The technologies of metallic conductors and making their coils have advanced rapidly, and also cooling technology has advanced, accordingly, superconductivity technology has reached the stage of practical use perfectly. (K.I.)

  2. Superconducting magnets and cryogenics for the steady state superconducting tokamak SST-1

    International Nuclear Information System (INIS)

    Saxena, Y.C.

    2000-01-01

    SST-1 is a steady state superconducting tokamak for studying the physics of the plasma processes in tokamak under steady state conditions and to learn technologies related to the steady state operation of the tokamak. SST-1 will have superconducting magnets made from NbTi based conductors operating at 4.5 K temperature. The design of the superconducting magnets and the cryogenic system of SST-1 tokamak are described. (author)

  3. Vector superconductivity in cosmic strings

    International Nuclear Information System (INIS)

    Dvali, G.R.; Mahajan, S.M.

    1992-03-01

    We argue that in most realistic cases, the usual Witten-type bosonic superconductivity of the cosmic string is automatically (independent of the existence of superconducting currents) accompanied by the condensation of charged gauge vector bosons in the core giving rise to a new vector type superconductivity. The value of the charged vector condensate is related with the charged scalar expectation value, and vanishes only if the latter goes to zero. The mechanism for the proposed vector superconductivity, differing fundamentally from those in the literature, is delineated using the simplest realistic example of the two Higgs doublet standard model interacting with the extra cosmic string. It is shown that for a wide range of parameters, for which the string becomes scalarly superconducting, W boson condensates (the sources of vector superconductivity) are necessarily excited. (author). 14 refs

  4. AlMn Transition Edge Sensors for Advanced ACTPol

    Science.gov (United States)

    Li, Dale; Austermann, Jason E.; Beall, James A.; Becker, Daniel T.; Duff, Shannon M.; Gallardo, Patricio A.; Henderson, Shawn W.; Hilton, Gene C.; Ho, Shuay-Pwu; Hubmayr, Johannes; Koopman, Brian J.; McMahon, Jeffrey J.; Nati, Federico; Niemack, Michael D.; Pappas, Christine G.; Salatino, Maria; Schmitt, Benjamin L.; Simon, Sara M.; Staggs, Suzanne T.; Van Lanen, Jeff; Ward, Jonathan T.; Wollack, Edward J.

    2016-07-01

    Advanced ACTPol (AdvACT) will use an array of multichroic polarization-sensitive AlMn transition edge sensor (TES) bolometers read out through time-division multiplexing. Aluminum doped with a low concentration of manganese can be deposited to a bulk film thickness for a more reliable superconducting critical temperature uniformity compared to thin bilayers. To build the TES, the AlMn alloy is deposited, over Nb wiring, to a specific thickness to set the TES normal resistance. The doping concentration of manganese coarsely defines the TES critical temperature, while a fine tuning is achieved by heating the deposited film to a specific temperature. The TES island is connected to the thermal bath via four silicon-nitride membranes, where their geometry defines the thermal conductance to the temperature of the bath. Lastly, the TES heat capacity is increased by addition of PdAu electrically connected to the AlMn film. Designs and performance characteristics of these AlMn TESs are presented for use in AdvACT.

  5. Stray light suppression in the Goddard IRAM 2-Millimeter Observer (GISMO)

    Science.gov (United States)

    Sharp, E. H.; Benford, D. J.; Fixsen, D. J.; Moseley, S. H.; Staguhn, J. G.; Wollack, E. J.

    2012-09-01

    The Goddard-IRAM Superconducting 2 Millimeter Observer (GISMO) is an 8x16 Transition Edge Sensor (TES) array of bolometers built as a pathfinder for TES detector development efforts at NASA Goddard Space Flight Center. GISMO has been used annually at the Institut de Radioastronomie Millimétrique (IRAM) 30 meter telescope since 2007 under engineering time and was opened in the spring of 2012 to the general astronomical community. The spring deployment provided an opportunity to modify elements of the room temperature optics before moving the instrument to its new permanent position in the telescope receiver cabin. This allowed for the possibility to extend the cryostat, introduce improved cold baffling and thus further optimize the stray light performance for final astronomical use of the instrument, which has been completed and validated. We will demonstrate and discuss several of the methods used to quantify and limit the influence of stray light in the GISMO camera.

  6. AlMn Transition Edge Sensors for Advanced ACTPol

    Science.gov (United States)

    Li, Dale; Austermann, Jason E.; Beall, James A.; Tucker, Daniel T.; Duff, Shannon M.; Gallardo, Patricio A.; Henderson, Shawn W.; Hilton, Gene C.; Ho, Shuay-Pwu; Hubmayr, Johannes; hide

    2016-01-01

    Advanced ACTPol (Adv ACT) will use an array of multichroic polarization sensitive AIMn transition edge sensor (TES) bolometers read out through time-division multiplexing. Aluminum doped with a low concentration of manganese can be deposited to a bulk film thickness for a more reliable superconducting critical temperature uniformity compared to thin bilayers. To build the TES, the AlMn alloy is deposited, over Nb wiring, to a specific thickness to set the TES normal resistance. The doping concentration of manganese coarsely defines the TES critical temperature, while a fine tuning is achieved by heating the deposited film to a specific temperature. The TES island is connected to the thermal bath via four silicon-nitride membranes, where their geometry defines the thermal conductance to the temperature of the bath. Lastly, the TES heat capacity is increased by addition of PdAu electrically connected to the AlMn film. Designs and performance characteristics of these AlMn TESs are presented for use in AdvACT.

  7. Growth and characterization of materials for infrared detectors and nonlinear optical switches; Proceedings of the Meeting, Orlando, FL, Apr. 2, 3, 1991

    Science.gov (United States)

    Longshore, Randolph E.; Baars, Jan W.

    Papers included in these proceedings are grouped under the topics of infrared material growth and characterization, infrared detector physics, and nonlinear optics. Attention is given to interface demarcation in Bridgman-Stockbarger crystal growth of II-VI compounds, growth of CdTe-CdMnTe heterostructures by molecular beam epitaxy, and a photoconductivity decay method for determining the minority carrier lifetime of p-type HgCdTe. Consideration is also given to anodic oxides on HgZnTe, the characterization of anodic fluoride films on Hg(1-x)Cd(x)Te, optical response in high-temperature superconducting thin films, and pyroelectric linear array IR detectors with CCD multiplexer. Other papers are on structural and optical properties of melt-processed calcium aluminate fibers, the preparation and characterization of a new thermistor material for thermistor bolometer, and photoemission from quantum-confined structure of nonlinear optical materials. (For individual items see A93-26893 to A93-26895)

  8. Current Redistribution around the Superconducting-to-normal Transition in Superconducting Nb-Ti Rutherford Cables

    CERN Document Server

    Willering, G P; ten Kate, H H J

    2008-01-01

    Sufficient thermal-electromagnetic stability against external heat sources is an essential design criterion for superconducting Rutherford cables, especially if operated close to the critical current. Due to the complex phenomena contributing to stability such as helium cooling, inter-strand current and heat transfer, its level is difficult to quantify. In order to improve our understanding, many stability tests were performed on different cable samples, each incorporating several point-like heaters. The current redistribution around the heat front is measured after inducing a local normal zone in one strand of the cable. By using voltage taps, expansion of the normal zone is monitored in the initially quenched strand as well as in adjacent strands. An array of Hall probes positioned at the cable edge is used to scan the selffield generated by the cable by which it becomes possible to estimate the inter-strand current transfer. In this paper it is demonstrated that two different stability regimes can be disti...

  9. Wire array K-shell sources on the SPHINX generator

    Science.gov (United States)

    D'Almeida, Thierry; Lassalle, Francis; Grunenwald, Julien; Maury, Patrick; Zucchini, Frédéric; Niasse, Nicolas; Chittenden, Jeremy

    2014-10-01

    The SPHINX machine is a LTD based Z-pinch driver operated by the CEA Gramat (France) and primarily used for studying K-shell radiation effects. We present the results of experiments carried out with single and nested large diameter aluminium wire array loads driven by a current of ~5 MA in ~800 ns. The dynamic of the implosion is studied with filtered X-UV time-integrated pin-hole cameras. The plasma electron temperature and the characteristics of the sources are estimated with time and spatially dependent spectrographs and PCDs. It is shown that Al K-shell yields (>1 keV) up to 27 kJ are obtained for a total radiation of ~ 230 kJ. These results are compared with simulations performed using the latest implementation of the non-LTE DCA code Spk in the 3D Eulerian MHD framework Gorgon developed at Imperial College. Filtered synthetic bolometers and PCD signals, time-dependent spatially integrated spectra and X-UV images are produced and show a good agreement with the experimental data. The capabilities of a prospective SPHINX II machine (20 MA ~ 800 ns) are also assessed for a wider variety of sources (Ti, Cu and W).

  10. Foreword: Focus on Superconductivity in Semiconductors

    Directory of Open Access Journals (Sweden)

    Yoshihiko Takano

    2008-01-01

    Full Text Available Since the discovery of superconductivity in diamond, much attention has been given to the issue of superconductivity in semiconductors. Because diamond has a large band gap of 5.5 eV, it is called a wide-gap semiconductor. Upon heavy boron doping over 3×1020 cm−3, diamond becomes metallic and demonstrates superconductivity at temperatures below 11.4 K. This discovery implies that a semiconductor can become a superconductor upon carrier doping. Recently, superconductivity was also discovered in boron-doped silicon and SiC semiconductors. The number of superconducting semiconductors has increased. In 2008 an Fe-based superconductor was discovered in a research project on carrier doping in a LaCuSeO wide-gap semiconductor. This discovery enhanced research activities in the field of superconductivity, where many scientists place particular importance on superconductivity in semiconductors.This focus issue features a variety of topics on superconductivity in semiconductors selected from the 2nd International Workshop on Superconductivity in Diamond and Related Materials (IWSDRM2008, which was held at the National Institute for Materials Science (NIMS, Tsukuba, Japan in July 2008. The 1st workshop was held in 2005 and was published as a special issue in Science and Technology of Advanced Materials (STAM in 2006 (Takano 2006 Sci. Technol. Adv. Mater. 7 S1.The selection of papers describe many important experimental and theoretical studies on superconductivity in semiconductors. Topics on boron-doped diamond include isotope effects (Ekimov et al and the detailed structure of boron sites, and the relation between superconductivity and disorder induced by boron doping. Regarding other semiconductors, the superconducting properties of silicon and SiC (Kriener et al, Muranaka et al and Yanase et al are discussed, and In2O3 (Makise et al is presented as a new superconducting semiconductor. Iron-based superconductors are presented as a new series of high

  11. Superconducting selenides intercalated with organic molecules: synthesis, crystal structure, electric and magnetic properties, superconducting properties, and phase separation in iron based-chalcogenides and hybrid organic-inorganic superconductors

    Science.gov (United States)

    Krzton-Maziopa, Anna; Pesko, Edyta; Puzniak, Roman

    2018-06-01

    Layered iron-based superconducting chalcogenides intercalated with molecular species are the subject of intensive studies, especially in the field of solid state chemistry and condensed matter physics, because of their intriguing chemistry and tunable electric and magnetic properties. Considerable progress in the research, revealing superconducting inorganic–organic hybrid materials with transition temperatures to superconducting state, T c, up to 46 K, has been brought in recent years. These novel materials are synthesized by low-temperature intercalation of molecular species, such as solvates of alkali metals and nitrogen-containing donor compounds, into layered FeSe-type structure. Both the chemical nature as well as orientation of organic molecules between the layers of inorganic host, play an important role in structural modifications and may be used for fine tuning of superconducting properties. Furthermore, a variety of donor species compatible with alkali metals, as well as the possibility of doping also in the host structure (either on Fe or Se sites), makes this system quite flexible and gives a vast array of new materials with tunable electric and magnetic properties. In this review, the main aspects of intercalation chemistry are discussed with a particular attention paid to the influence of the unique nature of intercalating species on the crystal structure and physical properties of the hybrid inorganic–organic materials. To get a full picture of these materials, a comprehensive description of the most effective chemical and electrochemical methods, utilized for synthesis of intercalated species, with critical evaluation of their strong and weak points, related to feasibility of synthesis, phase purity, crystal size and morphology of final products, is included as well.

  12. Status of RF superconductivity at Argonne

    International Nuclear Information System (INIS)

    Shepard, K.W.

    1990-01-01

    Development of a superconducting slow-wave structures began at Argonne National Laboratory (ANL) in 1971, and led to the first superconducting heavy-ion linac (ATLAS - the Argonne Tandem-Linac Accelerator System). The Physics Division at ANL has continued to develop superconducting RF technology for accelerating heavy-ions, with the result that the linac has been in an almost continuous process of upgrade and expansion. In 1987, the Engineering Physics Division at ANL began developing of superconducting RF components for the acceleration of high-brightness proton and deuterium beams. The two divisions collaborate in work on several applications of RF superconductivity, and also in work to develop the technology generally. The present report briefly describes major features of the superconducting heavy-ion linac (very-low-velocity superconducting linac, positive ion injector), proton accelerating structures (superconducting resonant cavities for acceleration of high-current proton and deuteron beams, RF properties of oxide superconductors), and future work. Both divisions expect to continue a variety of studies, frequently in collaboration, to advance the basic technology of RF superconductivity. (N.K.)

  13. Unconventional superconductivity in heavy-fermion compounds

    Energy Technology Data Exchange (ETDEWEB)

    White, B.D. [Department of Physics, University of California, San Diego, La Jolla, CA 92093 (United States); Center for Advanced Nanoscience, University of California, San Diego, La Jolla, CA 92093 (United States); Thompson, J.D. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Maple, M.B., E-mail: mbmaple@ucsd.edu [Department of Physics, University of California, San Diego, La Jolla, CA 92093 (United States); Center for Advanced Nanoscience, University of California, San Diego, La Jolla, CA 92093 (United States)

    2015-07-15

    Highlights: • Quasiparticles in heavy-fermion compounds are much heavier than free electrons. • Superconductivity involves pairing of these massive quasiparticles. • Quasiparticle pairing mediated by magnetic or quadrupolar fluctuations. • We review the properties of superconductivity in heavy-fermion compounds. - Abstract: Over the past 35 years, research on unconventional superconductivity in heavy-fermion systems has evolved from the surprising observations of unprecedented superconducting properties in compounds that convention dictated should not superconduct at all to performing explorations of rich phase spaces in which the delicate interplay between competing ground states appears to support emergent superconducting states. In this article, we review the current understanding of superconductivity in heavy-fermion compounds and identify a set of characteristics that is common to their unconventional superconducting states. These core properties are compared with those of other classes of unconventional superconductors such as the cuprates and iron-based superconductors. We conclude by speculating on the prospects for future research in this field and how new advances might contribute towards resolving the long-standing mystery of how unconventional superconductivity works.

  14. Superconducting wires and methods of making thereof

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Xingchen; Sumption, Michael D.; Peng, Xuan

    2018-03-13

    Disclosed herein are superconducting wires. The superconducting wires can comprise a metallic matrix and at least one continuous subelement embedded in the matrix. Each subelement can comprise a non-superconducting core, a superconducting layer coaxially disposed around the non-superconducting core, and a barrier layer coaxially disposed around the superconducting layer. The superconducting layer can comprise a plurality of Nb.sub.3Sn grains stabilized by metal oxide particulates disposed therein. The Nb.sub.3Sn grains can have an average grain size of from 5 nm to 90 nm (for example, from 15 nm to 30 nm). The superconducting wire can have a high-field critical current density (J.sub.c) of at least 5,000 A/mm.sup.2 at a temperature of 4.2 K in a magnetic field of 12 T. Also described are superconducting wire precursors that can be heat treated to prepare superconducting wires, as well as methods of making superconducting wires.

  15. Performance of a novel SQUID-based superconducting imaging-surface magnetoencephalography system

    Science.gov (United States)

    Kraus, R. H.; Volegov, P.; Maharajh, K.; Espy, M. A.; Matlashov, A. N.; Flynn, E. R.

    2002-03-01

    Performance for a recently completed whole-head magnetoencephalography system using a superconducting imaging surface (SIS) surrounding an array of 150 SQUID magnetometers is reported. The helmet-like SIS is hemispherical in shape with a brim. Conceptually, the SIS images nearby sources onto the SQUIDs while shielding sensors from distant “noise” sources. A finite element method (FEM) description using the as-built geometry was developed to describe the SIS effect on source fields by imposing B⊥( surface)=0 . Sensors consist of 8×8 mm 2 SQUID magnetometers with 0.84 nT/ Φ0 sensitivity and positions and orientations was found. Good agreement was found between modeled and measured shielding of the SQUIDs from sources external to the array showing significant frequency-independent shielding. Phantom localization precision was better than 0.5 mm at all locations with a mean of better than 0.3 mm.

  16. Superconducting magnet development in Japan

    International Nuclear Information System (INIS)

    Yasukochi, K.

    1983-01-01

    The present state of R and D works on the superconducting magnet and its applications in Japan are presented. On electrical rotating machines, 30 MVA superconducting synchronous rotary condenser (Mitsubishi and Fuji) and 50 MVA generator are under construction. Two ways of ship propulsion by superconducting magnets are developing. A superconducting magnetically levitated and linear motor propelled train ''MAGLEV'' was developed by the Japan National Railways (JNR). The superconducting magnet development for fusion is the most active field in Japan. The Cluster Test program has been demonstrated on a 10 T Nb 3 Sn coil and the first coil of Large Coil Task in IEA collaboration has been constructed and the domestic test was completed in JAERI. These works are for the development of toroidal coils of the next generation tokamak machine. R and D works on superconducting ohmic heating coil are in progress in JAERI and ETL. The latter group has constructed 3.8 MJ pulsed coil. A high ramp rate of changing field in pulsed magnet, 200 T/s, has been tested successfully. High Energy Physics Laboratory (KEK) are conducting active works. The superconducting μ meson channel and π meson channel have been constructed and are operating successfully. KEK has also a project of big accelerator named ''TRISTAN'', which is similar to ISABELLE project of BNL. Superconducting synchrotron magnets are developed for this project. The development of superconducting three thin wall solenoid has been started. One of them, CDF, is progressing under USA-Japan collaboration

  17. Superconducting joint of Bi-2223/Ag superconducting tapes by diffusion bonding

    International Nuclear Information System (INIS)

    Guo Wei; Zou Guisheng; Wu Aiping; Wang Yanjun; Bai Hailin; Ren Jialie

    2009-01-01

    61-Filaments Bi-2223/Ag superconducting tapes have been joined by diffusion bonding. The critical currents (I C s) of the joints are obtained by using standard four probe method under no magnetic field in the liquid nitrogen. The microstructures of the joints are evaluated by the electron microscope in electron backscatter diffraction mode and the phase compositions of the superconducting cores of the joint and the original tape are determined by X-ray diffraction (XRD). The results show diffusion bonding is effective bonding technique for HTS tapes, and the bonding time is reduced greatly from hundreds of hours to a few hours, and the bonding pressure also changes from 140-4000 MPa to 3 MPa. Furthermore, the diffusion bonding joints sustain superconducting properties, and the critical current ratios (CCR O ) of the joints are in the range of 35%-80%. Microstructures of the typical joint display a good bonding and some defects existed in traditional method are avoided. XRD results show that the phase compositions of the superconducting cores have no obvious changes before and after diffusion bonding, which offers physical and material bases for high superconducting property of the joints.

  18. Superconductivity in the 1990's

    International Nuclear Information System (INIS)

    Stekly, Z.J.J.

    1990-01-01

    Superconducting magnets, coils or windings are the basis for a range of major applications in the energy area such as energy storage in superconducting coils, magnets for fusion research, and rotating machinery. Other major applications of superconductivity include high energy physics where 1000 superconducting magnets are operated continuously in the Tevatron at Fermilab in Illinois, over 12,000 superconducting magnets will be required for the superconducting Super Collider being build near Dallas. The largest commercial application of superconductors is in magnets for magnetic resonance imaging (MRI) - a new medical diagnostic imaging technique with about 2,000 systems installed worldwide. These form a sizable technology base on which to evaluate and push forward applications such as magneto hydrodynamic propulsion of seagoing vessels. The attractiveness of which depends ultimately on the characteristics of the superconducting magnet. The magnet itself is a combination of several technology areas - the conductors, magnetics, structures and cryogenics. This paper reviews state-of-the-art in each of the technology areas as they relate to superconductors

  19. Superconductivity in doped Dirac semimetals

    Science.gov (United States)

    Hashimoto, Tatsuki; Kobayashi, Shingo; Tanaka, Yukio; Sato, Masatoshi

    2016-07-01

    We theoretically study intrinsic superconductivity in doped Dirac semimetals. Dirac semimetals host bulk Dirac points, which are formed by doubly degenerate bands, so the Hamiltonian is described by a 4 ×4 matrix and six types of k -independent pair potentials are allowed by the Fermi-Dirac statistics. We show that the unique spin-orbit coupling leads to characteristic superconducting gap structures and d vectors on the Fermi surface and the electron-electron interaction between intra and interorbitals gives a novel phase diagram of superconductivity. It is found that when the interorbital attraction is dominant, an unconventional superconducting state with point nodes appears. To verify the experimental signature of possible superconducting states, we calculate the temperature dependence of bulk physical properties such as electronic specific heat and spin susceptibility and surface state. In the unconventional superconducting phase, either dispersive or flat Andreev bound states appear between point nodes, which leads to double peaks or a single peak in the surface density of states, respectively. As a result, possible superconducting states can be distinguished by combining bulk and surface measurements.

  20. Superconductivity: materials and applications

    International Nuclear Information System (INIS)

    Duchateau, J.L.; Kircher, F.; Leveque, J.; Tixador, P.

    2008-01-01

    This digest paper presents the different types of superconducting materials: 1 - the low-TC superconductors: the multi-filament composite as elementary constituent, the world production of NbTi, the superconducting cables of the LHC collider and of the ITER tokamak; 2 - the high-TC superconductors: BiSrCaCuO (PIT 1G) ribbons and wires, deposited coatings; 3 - application to particle physics: the the LHC collider of the CERN, the LHC detectors; 4 - applications to thermonuclear fusion: Tore Supra and ITER tokamaks; 5 - NMR imaging: properties of superconducting magnets; 6 - applications in electrotechnics: cables, motors and alternators, current limiters, transformers, superconducting energy storage systems (SMES). (J.S.)

  1. Superconductivity in power engineering

    International Nuclear Information System (INIS)

    1989-01-01

    This proceedings volume presents 24 conference papers and 15 posters dealing with the following aspects: 1) Principles and elementary aspects of high-temperature superconductivity (3 plenary lectures); 2) Preparation, properties and materials requirements of metallic or oxide superconductors (critical current behaviour, soldered joints, structural studies); 3) Magnet technology (large magnets for thermonuclear fusion devices; magnets for particle accelerators and medical devices); 4) Magnetic levitation and superconductivity; 5) Cryogenics; 6) Energy storage systems using superconducting coils (SMES); 7) Superconducting power transmission cables, switches, transformers, and generator systems for power plant; 8) Supporting activities, industrial aspects, patents. There are thirty-eight records in the ENERGY database relating to individual conference papers. (MM) [de

  2. NTD germanium: a novel material for low-temperature bolometers

    International Nuclear Information System (INIS)

    Haller, E.E.; Palaio, N.P.; Rodder, M.; Hansen, W.L.; Kreysa, E.

    1982-06-01

    Six samples of ultra-pure (absolute value N/sub A/ - N/sub D/ absolute value less than or equal to 10 11 cm -3 ), single-crystal germanium have been neutron transmutation doped with neutron doses between 7.5 x 10 16 and 1.88 x 10 18 cm -2 . After thermal annealing at 400 0 C for six hours in a pure argon atmosphere, the samples have been characterized with Hall effect and resistivity measurements between 300 and 0.3 K. Our results show that the resistivity in the low temperature, hopping conduction regime can be approximated with rho = rho 0 exp(Δ/T). The three more heavily doped samples show values for rho 0 and Δ ranging from 430 to 3.3 Ω cm and from 4.9 to 2.8 K, respectively. The excellent reproducibility of neutron transmutation doping and the values of rho 0 and Δ make NTD Ge a prime candidate for the fabrication of low temperature, low noise bolometers. The large variation in the tabulated values of the thermal neutron cross sections for the different germanium isotopes makes it clear that accurate measurements of these cross-sections for well defined neutron energy spectra would be highly desirable

  3. High-Tc superconducting electric motors

    International Nuclear Information System (INIS)

    Schiferl, R.; Stein, J.

    1992-01-01

    In this paper, the advantages and limitations of using superconductors in motors are discussed. A synchronous motor with a high temperature superconducting field winding for pump and fan drive applications is described and some of its unique design features are identified. A 10,000 horsepower superconducting motor design is presented. The critical field and current density requirements for high temperature superconducting wire in motors is discussed. Finally, recent progress in superconducting wire performance is presented

  4. MgB2 thin-film bolometer for applications in far-infrared instruments on future planetary missions

    International Nuclear Information System (INIS)

    Lakew, B.; Aslam, S.; Brasunas, J.; Cao, N.; Costen, N.; La, A.; Nguyen, L.; Stevenson, T.; Waczynski, A.

    2012-01-01

    A SiN membrane based MgB 2 thin-film bolometer, with a non-optimized absorber, has been fabricated that shows an electrical noise equivalent power of 2.56 × 10 -13 W/√Hz operating at 30 Hz and a responsivity of 702 kV/W. It is predicted that with the inclusion of a gold black absorber that an optical specific detectivity of 8.3 × 10 10 cm/√Hz/W at an operational frequency of 10 Hz, can be realized for integration into future planetary exploration instrumentation where high sensitivity is required in the 17-250 μm spectral wavelength range.

  5. Application of the BRF system to some superconducting magnet design problems

    International Nuclear Information System (INIS)

    Meuser, R.B.

    1974-01-01

    The Berkeley Remote Facility (BRF) system--affected through a system of teletype terminals linked to the LBL computers--was used to solve a large number of magnetic-field problems associated with the design and analysis of superconducting beam-transport magnets. The limitations of the BRF system are severe: total storage, 1000; 10 subscripted variables; no integer or complex arithmetic; no function or subroutine subprograms except those in its Spartan library; and a pidgin Fortran language. However, for fully 90 percent of the computational work, the low IQ of the BRF was more than counter-balanced by its being on-line. The magnets built have a long cylindrical aperture surrounded by arrays of longitudinal superconducting wires and iron arranged to produce a transverse field of prescribed shape, uniform fields for bending high energy charged particle beams, and quarupole fields for focusing. The field in the aperture is expressed, usually, in terms of the coefficients of the Taylor's expansion--the ''multipole coefficients''. Point values of the field vector are also of interest, especially within the windings, as the magnitude of the field determines the allowable current. Many small programs were developed to analyze both the two- and three-dimensional fields produced by various kinds of arrays of conductors. Some programs have the ability to vary a number of geometric parameters automatically in such a way as to drive the same number of multipole coefficients to zero. The on-line feature is especially handy, as such iterative calculations must often be cajoled into convergence. (U.S.)

  6. Superconducting magnets for a muon collider

    International Nuclear Information System (INIS)

    Green, M.A.

    1996-01-01

    The existence of a muon collider will be dependent on the use of superconducting magnets. Superconducting magnets for the μ - μ + collider will be found in the following locations: the π - π + capture system, the muon phase rotation system, the muon cooling system, the recirculating acceleration system, the collider ring, and the collider detector system. This report describes superconducting magnets for each of these sections except the detector. In addition to superconducting magnets, superconducting RF cavities will be found in the recirculating accelerator sections and the collider ring. The use of superconducting magnets is dictated by the need for high magnetic fields in order to reduce the length of various machine components. The performance of all of the superconducting magnets will be affected the energy deposited from muon decay products. (orig.)

  7. High-resolution photon spectroscopy with a microwave-multiplexed 4-pixel transition edge sensor array

    Science.gov (United States)

    Guss, Paul; Rabin, Michael; Croce, Mark; Hoteling, Nathan; Schwellenbach, David; Kruschwitz, Craig; Mocko, Veronika; Mukhopadhyay, Sanjoy

    2017-09-01

    We demonstrate very high-resolution photon spectroscopy with a microwave-multiplexed 4-pixel transition edge sensor (TES) array. The readout circuit consists of superconducting microwave resonators coupled to radio frequency superconducting-quantum-interference devices (RF-SQUIDs) and transduces changes in input current to changes in phase of a microwave signal. We used a flux-ramp modulation to linearize the response and avoid low-frequency noise. The result is a very high-resolution photon spectroscopy with a microwave-multiplexed 4-pixel transition edge sensor array. We performed and validated a small-scale demonstration and test of all the components of our concept system, which encompassed microcalorimetry, microwave multiplexing, RF-SQUIDs, and software-defined radio (SDR). We shall display data we acquired in the first simultaneous combination of all key innovations in a 4-pixel demonstration, including microcalorimetry, microwave multiplexing, RF-SQUIDs, and SDR. We present the energy spectrum of a gadolinium-153 (153Gd) source we measured using our 4-pixel TES array and the RF-SQUID multiplexer. For each pixel, one can observe the two 97.4 and 103.2 keV photopeaks. We measured the 153Gd photon source with an achieved energy resolution of 70 eV, full width half maximum (FWHM) at 100 keV, and an equivalent readout system noise of 90 pA/pHz at the TES. This demonstration establishes a path for the readout of cryogenic x-ray and gamma ray sensor arrays with more elements and spectral resolving powers. We believe this project has improved capabilities and substantively advanced the science useful for missions such as nuclear forensics, emergency response, and treaty verification through the explored TES developments.

  8. rf power dependence of subharmonic voltage spectra of two-dimensional Josephson-junction arrays

    International Nuclear Information System (INIS)

    Hebboul, S.E.; Garland, J.C.

    1993-01-01

    We have measured the rf-bias-current dependence of the ν/2 subharmonic spectral response of planar 300x300 Nb-Au-Nb proximity-coupled Josephson-junction arrays. The ν/2 subharmonic voltage spectrum was examined at two rf-bias frequencies, ν/ν c ∼1.4, 2.0 (ν c ∼120 MHz), and in applied magnetic fields corresponding to f=0,1/2 flux quantum per plaquette. The measurements were compared to analytical predictions for an rf-biased asymmetric superconducting quantum interference device with non-negligble loop inductance and large rf-bias-current amplitudes, based on the resistively shunted Josephson-junction model. Reasonable agreement was found between experiment and theory, suggesting that a possible origin for the observed subharmonic behavior in arrays involves an interplay between array plaquette inductances and junction critical-current variations

  9. Tunable pinning effects produced by non-uniform antidot arrays in YBCO thin films

    Energy Technology Data Exchange (ETDEWEB)

    George, J.; Jones, A.; Al-Qurainy, M. [Institute for Superconducting and Electronic Materials, University of Wollongong, NSW (Australia); Fedoseev, S.A. [Institute for Superconducting and Electronic Materials, University of Wollongong, NSW (Australia); Centre for Medical Radiation Physics, University of Wollongong, NSW (Australia); Rosenfeld, A. [Centre for Medical Radiation Physics, University of Wollongong, NSW (Australia); Pan, A.V. [Institute for Superconducting and Electronic Materials, University of Wollongong, NSW (Australia); National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow (Russian Federation)

    2017-04-15

    Uniform, graded and spaced arrays of 3 μm triangular antidots in pulsed laser deposited YBa{sub 2}Cu{sub 3}O{sub 7} (YBCO) superconducting thin films are compared by examining the improvements in the critical current density J{sub c} they produced. The comparison is made to establish the role of their lithographically defined (non-)uniformity and the effectiveness to control and/or enhance the critical current density. It is found that almost all types of non-uniform arrays, including graded ones enhance J{sub c} over the broad applied magnetic field and temperature range due to the modified critical state. Whereas uniform arrays of antidots either reduce or produce no effect on J{sub c} compared to the original (as-deposited) thin films. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Superconducting wind turbine generators

    DEFF Research Database (Denmark)

    Abrahamsen, Asger Bech; Mijatovic, Nenad; Seiler, Eugen

    2010-01-01

    , the main challenge of the superconducting direct drive technology is to prove that the reliability is superior to the alternative drive trains based on gearboxes or permanent magnets. A strategy of successive testing of superconducting direct drive trains in real wind turbines of 10 kW, 100 kW, 1 MW and 10......We have examined the potential of 10 MW superconducting direct drive generators to enter the European offshore wind power market and estimated that the production of about 1200 superconducting turbines until 2030 would correspond to 10% of the EU offshore market. The expected properties of future...... offshore turbines of 8 and 10 MW have been determined from an up-scaling of an existing 5 MW turbine and the necessary properties of the superconducting drive train are discussed. We have found that the absence of the gear box is the main benefit and the reduced weight and size is secondary. However...

  11. Three-terminal superconducting devices

    International Nuclear Information System (INIS)

    Gallagher, W.J.

    1985-01-01

    The transistor has a number of properties that make it so useful. The authors discuss these and the additional properties a transistor would need to have for high performance applications at temperatures where superconductivity could contribute advantages to system-level performance. These properties then serve as criteria by which to evaluate three-terminal devices that have been proposed for applications at superconducting temperatures. FETs can retain their transistor properties at low temperatures, but their power consumption is too large for high-speed, high-density cryogenic applications. They discuss in detail why demonstrated superconducting devices with three terminals -Josephson effect based devices, injection controlled weak links, and stacked tunnel junction devices such as the superconducting transistor proposed by K. Gray and the quiteron -- each fail to have true transistor-like properties. They conclude that the potentially very rewarding search for a transistor compatible with superconductivity in high performance applications must be in new directions

  12. Korea's developmental program for superconductivity

    Science.gov (United States)

    Hong, Gye-Won; Won, Dong-Yeon; Kuk, Il-Hyun; Park, Jong-Chul

    1995-04-01

    Superconductivity research in Korea was firstly carried out in the late 70's by a research group in Seoul National University (SNU), who fabricated a small scale superconducting magnetic energy storage system under the financial support from Korea Electric Power Company (KEPCO). But a few researchers were involved in superconductivity research until the oxide high Tc superconductor was discovered by Bednorz and Mueller. After the discovery of YBaCuO superconductor operating above the boiling point of liquid nitrogen (77 K)(exp 2), Korean Ministry of Science and Technology (MOST) sponsored a special fund for the high Tc superconductivity research to universities and national research institutes by recognizing its importance. Scientists engaged in this project organized 'High Temperature Superconductivity Research Association (HITSRA)' for effective conducting of research. Its major functions are to coordinate research activities on high Tc superconductivity and organize the workshop for active exchange of information. During last seven years the major superconductivity research has been carried out through the coordination of HITSRA. The major parts of the Korea's superconductivity research program were related to high temperature superconductor and only a few groups were carrying out research on conventional superconductor technology, and Korea Atomic Energy Research Institute (KAERI) and Korea Electrotechnology Research Institute (KERI) have led this research. In this talk, the current status and future plans of superconductivity research in Korea will be reviewed based on the results presented in interim meeting of HITSRA, April 1-2, 1994. Taejeon, as well as the research activity of KAERI.

  13. Superconducting machines. Chapter 4

    International Nuclear Information System (INIS)

    Appleton, A.D.

    1977-01-01

    A brief account is given of the principles of superconductivity and superconductors. The properties of Nb-Ti superconductors and the method of flux stabilization are described. The basic features of superconducting d.c. machines are illustrated by the use of these machines for ship propulsion, steel-mill drives, industrial drives, aluminium production, and other d.c. power supplies. Superconducting a.c. generators and their design parameters are discussed. (U.K.)

  14. Superconductivity at the industrial scale

    International Nuclear Information System (INIS)

    Tixador, P.; Lebrun, Ph.

    2011-01-01

    The discovery of superconductivity is 100 years old but theoretical works are still necessary: the BCS theory does not apply to the new families of high temperature superconducting materials discovered after 1986. In 2001 it was discovered that MgB 2 is superconducting at 39 K, this critical temperature is not the highest but MgB 2 is easy to produce and cheap. Today's highest critical temperature under atmospheric pressure is that of the HgTlBaCaCuO compound: 138 K. The complexity and the cost of cryogenic systems restrain the applications of superconductivity. The author reviews the applications of superconducting in medical imaging, particle detectors, and in the safety systems of power networks. (A.C.)

  15. Process of producing superconducting bar magnets

    International Nuclear Information System (INIS)

    Wilson, M.A.

    1988-01-01

    A method of forming a magnet having an established magnetic field is described comprising; (1) establishing a magnetic field of the desired extent and shape; (2) providing a superconducting material of desired shape; (3) positioning the material of (2) in field (1) while at a temperature above the critical temperature of the superconducting material so as to apply a magnetic field on the superconducting material; (4) cooling the superconducting material while in magnetic field (1) to below the critical temperature of the superconducting material; (5) removing the superconducting material from the magnetic field while in the supercooled condition; and (6) maintaining the material at or below the critical temperature

  16. Challenges, constraints, and results of lens design for 17 micron-bolometer focal plane arrays in 8-12 micron waveband

    Science.gov (United States)

    Schuster, Norbert; Franks, John

    2011-06-01

    In the 8-12 micron waveband Focal Plane Arrays (FPA) are available with a 17 micron pixel pitch in different arrays sizes (e.g. 512 x 480 pixels and 320 x 240 pixels) and with excellent electrical properties. Many applications become possible using this new type of IR-detector which will become the future standard in uncooled technology. Lenses with an f-number faster than f/1.5 minimize the diffraction impact on the spatial resolution and guarantee a high thermal resolution for uncooled cameras. Both effects will be quantified. The distinction between Traditional f-number (TF) and Radiometric f-number (RF) is discussed. Lenses with different focal lengths are required for applications in a variety of markets. They are classified by their Horizontal field of view (HFOV). Respecting the requirements for high volume markets, several two lens solutions will be discussed. A commonly accepted parameter of spatial resolution is the Modulation Transfer Function (MTF)-value at the Nyquist frequency of the detector (here 30cy/mm). This parameter of resolution will be presented versus field of view. Wide Angle and Super Wide Angle lenses are susceptible to low relative illumination in the corner of the detector. Measures to reduce this drop to an acceptable value are presented.

  17. Superconductivity and its devices

    International Nuclear Information System (INIS)

    Forbes, D.S.

    1981-01-01

    Among the more important developments that are discussed are cryotrons, superconducting motors and generators, and high-field magnets. Cryotrons will create faster and more economical computer systems. Superconducting motors and generators will cost much less to build than conventional electric generators and cut fuel consumption. Moreover, high-field magnets are being used to confine plasma in connection with nuclear fusion. Superconductors have a vital role to play in all of these developments. Most importantly, though, are the magnetic properties of superconductivity. Superconducting magnets are an integral part of nuclear fusion. In addition, high-field magnets are necessary in the use of accelerators, which are needed to study the interactions between elementary particles

  18. Superconductivity

    CERN Document Server

    Poole, Charles P; Creswick, Richard J; Prozorov, Ruslan

    2014-01-01

    Superconductivity, Third Edition is an encyclopedic treatment of all aspects of the subject, from classic materials to fullerenes. Emphasis is on balanced coverage, with a comprehensive reference list and significant graphics from all areas of the published literature. Widely used theoretical approaches are explained in detail. Topics of special interest include high temperature superconductors, spectroscopy, critical states, transport properties, and tunneling. This book covers the whole field of superconductivity from both the theoretical and the experimental point of view. This third edition features extensive revisions throughout, and new chapters on second critical field and iron based superconductors.

  19. Superconducting elliptical cavities

    CERN Document Server

    Sekutowicz, J K

    2011-01-01

    We give a brief overview of the history, state of the art, and future for elliptical superconducting cavities. Principles of the cell shape optimization, criteria for multi-cell structures design, HOM damping schemes and other features are discussed along with examples of superconducting structures for various applications.

  20. Unconventional superconductivity in honeycomb lattice

    Directory of Open Access Journals (Sweden)

    P Sahebsara

    2013-03-01

    Full Text Available   ‎ The possibility of symmetrical s-wave superconductivity in the honeycomb lattice is studied within a strongly correlated regime, using the Hubbard model. The superconducting order parameter is defined by introducing the Green function, which is obtained by calculating the density of the electrons ‎ . In this study showed that the superconducting order parameter appears in doping interval between 0 and 0.5, and x=0.25 is the optimum doping for the s-wave superconductivity in honeycomb lattice.

  1. Equilibrium vortex structures of type-II/1 superconducting films with washboard pinning landscapes

    Science.gov (United States)

    Wei, C. A.; Xu, X. B.; Xu, X. N.; Wang, Z. H.; Gu, M.

    2018-05-01

    We numerically study the equilibrium vortex structures of type-II/1 superconducting films with a periodic quasi-one-dimensional corrugated substrate. We show as a function of substrate period and pinning strength that, the vortex system displays a variety of vortex phases including arrays consisted of vortex clumps with different morphologies, ordered vortex stripes parallel and perpendicular to pinning troughs, and ordered one-dimensional vortex chains. Our simulations are helpful in understanding the structural modulations for extensive systems with both competing interactions and competing periodicities.

  2. 2017 Gordon Conference on Superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Chubukov, Andrey [Univ. of Minnesota, Twin Cities, MN (United States)

    2017-11-14

    The DOE award was for a 2017 Gordon Research conference on Superconductivity (GRC). The objective of GRC is to interchange the information about the latest theoretical and experimental developments in the area of superconductivity and to select most perspective directions for future research in this area.The goal of the Gordon Conference on Superconductivity is to present and discuss the latest results in the field of modern superconductivity, discuss new ideas and new directions of research in the area. It is a long-standing tradition of the Gordon conference on Superconductivity that the vast majority of participants are junior scientists. Funding for the conference would primarily be used to support junior researchers, particularly from under-represented groups. We had more 10 female speakers, some of them junior researchers, and some funding was used to support these speakers. The conference was held together with Gordon Research Seminar on Superconductivity, where almost all speakers and participants were junior scientists.

  3. Superconducting energy storage magnet

    Science.gov (United States)

    Boom, Roger W. (Inventor); Eyssa, Yehia M. (Inventor); Abdelsalam, Mostafa K. (Inventor); Huang, Xianrui (Inventor)

    1993-01-01

    A superconducting magnet is formed having composite conductors arrayed in coils having turns which lie on a surface defining substantially a frustum of a cone. The conical angle with respect to the central axis is preferably selected such that the magnetic pressure on the coil at the widest portion of the cone is substantially zero. The magnet structure is adapted for use as an energy storage magnet mounted in an earthen trench or tunnel where the strength the surrounding soil is lower at the top of the trench or tunnel than at the bottom. The composite conductor may be formed having a ripple shape to minimize stresses during charge up and discharge and has a shape for each ripple selected such that the conductor undergoes a minimum amount of bending during the charge and discharge cycle. By minimizing bending, the working of the normal conductor in the composite conductor is minimized, thereby reducing the increase in resistance of the normal conductor that occurs over time as the conductor undergoes bending during numerous charge and discharge cycles.

  4. Superconductivity in doped fullerenes

    International Nuclear Information System (INIS)

    Hebard, A.F.

    1992-01-01

    While there is not complete agreement on the microscopic mechanism of superconductivity in alkali-metal-doped C 60 , further research may well lead to the production of analogous materials that lose resistance at even higher temperatures. Carbon 60 is a fascinating and arrestingly beautiful molecule. With 12 pentagonal and 20 hexagonal faces symmetrically arrayed in a soccer-ball-like structure that belongs to the icosahedral point group, I h , its high symmetry alone invites special attention. The publication in September 1990 of a simple technique for manufacturing and concentrating macroscopic amounts of this new form of carbon announced to the scientific community that enabling technology had arrived. Macroscopic amounts of C 60 (and the higher fullerenes, such as C 70 and C 84 ) can now be made with an apparatus as simple as an arc furnace powered with an arc welding supply. Accordingly, chemists, physicists and materials scientists have joined forces in an explosion of effort to explore the properties of this unusual molecular building block. 23 refs., 6 figs

  5. Superconductivity in doped fullerenes

    International Nuclear Information System (INIS)

    Herbard, A.F.

    1996-01-01

    While there is not complete agreement on the microscopic mechanism of superconductivity in alkali-metal-doped C sup 0, further research may well lead to the production of analogous materials that lose resistance at even higher temperatures. Carbon 60 is a fascinating and arrestingly beautiful molecule. With 12 pentagonal and 20 hexagonal faces symmetrically arrayed in a soccer-ball-like structure that belongs to the icosahedral point group, I sub h, its high symmetry alone invites special attention. The publication in september 1990 of a simple technique for manufacturing and concentrating macroscopic amounts of this new form of carbon announced to the scientific community that enabling technology had arrived. Macroscopic amounts of C sub 6 sub 0 (and the higher fullerenes, such as C sub 7 sub 0 and C sub 8 sub 4) can now be made with an apparatus as simple as an arc furnace powered with an arc welding supply. Accordingly, chemists, physicists and materials scientists have joined forces in an explosion of effort to explore the properties of this unusual molecular building block. (author). 23 refs., 6 figs

  6. Superconductivity and their applications

    OpenAIRE

    Roque, António; Sousa, Duarte M.; Fernão Pires, Vítor; Margato, Elmano

    2017-01-01

    Trabalho apresentado em International Conference on Renewable Energies and Power Quality (ICREPQ’17), 4 a 6 de Abril de 2017, Málaga, Espanha The research in the field of superconductivity has led to the synthesis of superconducting materials with features that allow you to expand the applicability of this kind of materials. Among the superconducting materials characteristics, the critical temperature of the superconductor is framing the range and type of industrial applications that can b...

  7. Superconducting wind turbine generators

    International Nuclear Information System (INIS)

    Abrahamsen, A B; Seiler, E; Zirngibl, T; Andersen, N H; Mijatovic, N; Traeholt, C; Pedersen, N F; Oestergaard, J; Noergaard, P B

    2010-01-01

    We have examined the potential of 10 MW superconducting direct drive generators to enter the European offshore wind power market and estimated that the production of about 1200 superconducting turbines until 2030 would correspond to 10% of the EU offshore market. The expected properties of future offshore turbines of 8 and 10 MW have been determined from an up-scaling of an existing 5 MW turbine and the necessary properties of the superconducting drive train are discussed. We have found that the absence of the gear box is the main benefit and the reduced weight and size is secondary. However, the main challenge of the superconducting direct drive technology is to prove that the reliability is superior to the alternative drive trains based on gearboxes or permanent magnets. A strategy of successive testing of superconducting direct drive trains in real wind turbines of 10 kW, 100 kW, 1 MW and 10 MW is suggested to secure the accumulation of reliability experience. Finally, the quantities of high temperature superconducting tape needed for a 10 kW and an extreme high field 10 MW generator are found to be 7.5 km and 1500 km, respectively. A more realistic estimate is 200-300 km of tape per 10 MW generator and it is concluded that the present production capacity of coated conductors must be increased by a factor of 36 by 2020, resulting in a ten times lower price of the tape in order to reach a realistic price level for the superconducting drive train.

  8. Tailoring the High-Q LC Filter Arrays for Readout of Kilo-Pixel TES Arrays in the SPICA-SAFARI Instrument

    Science.gov (United States)

    Bruijn, M. P.; Gottardi, L.; den Hartog, R. H.; van der Kuur, J.; van der Linden, A. J.; Jackson, B. D.

    2014-08-01

    Following earlier presentations of arrays of high quality factor (Q 10.000) superconducting resonators in the MHz regime, we report on improvement of the packing density of resonance frequencies to 160 in the 1-3 MHz band. Spread in the spacing of resonances is found to be limited to 1 kHz (1 with the present fabrication procedure. The present packing density of frequencies and chip area approaches the requirements for the SAFARI instrument on the SPICA mission (in preparation). The a-Si:H dielectric layer in the planar S-I-S capacitors shows a presently unexplained apparent negative effective series resistance, depending on operating temperature and applied testing voltage.

  9. Superconducting Kinetic Inductance Detectors for astronomy and particle physics

    International Nuclear Information System (INIS)

    Calvo, M.; Goupy, J.; D'Addabbo, A.; Benoit, A.; Bourrion, O.; Catalano, A.; Monfardini, A.

    2016-01-01

    Kinetic Inductance Detectors (KID) represent a novel detector technology based on superconducting resonators. Since their first demonstration in 2003, they have been rapidly developed and are today a strong candidate for present and future experiments in the different bands of the electromagnetic spectrum. This has been possible thanks to the unique features of such devices: in particular, they couple a very high sensitivity to their intrinsic suitability for frequency domain multiplexed readout, making the fabrication of large arrays of ultrasensitive detectors possible. There are many fields of application that can profit of such detectors. Here, we will briefly review the principle of operation of a KID, and give two sample applications, to mm-wave astronomy and to particle physics.

  10. Superconducting Kinetic Inductance Detectors for astronomy and particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Calvo, M., E-mail: martino.calvo@neel.cnrs.fr [Institute Néel, CNRS, Grenoble (France); Goupy, J.; D' Addabbo, A.; Benoit, A. [Institute Néel, CNRS, Grenoble (France); Bourrion, O. [Laboratoire de Physique Subatomique et Cosmologie, CNRS, Grenoble (France); Catalano, A. [Institute Néel, CNRS, Grenoble (France); Laboratoire de Physique Subatomique et Cosmologie, CNRS, Grenoble (France); Monfardini, A. [Institute Néel, CNRS, Grenoble (France)

    2016-07-11

    Kinetic Inductance Detectors (KID) represent a novel detector technology based on superconducting resonators. Since their first demonstration in 2003, they have been rapidly developed and are today a strong candidate for present and future experiments in the different bands of the electromagnetic spectrum. This has been possible thanks to the unique features of such devices: in particular, they couple a very high sensitivity to their intrinsic suitability for frequency domain multiplexed readout, making the fabrication of large arrays of ultrasensitive detectors possible. There are many fields of application that can profit of such detectors. Here, we will briefly review the principle of operation of a KID, and give two sample applications, to mm-wave astronomy and to particle physics.

  11. An Ultrasensitive Hot-Electron Bolometer for Low-Background SMM Applications

    Science.gov (United States)

    Olayaa, David; Wei, Jian; Pereverzev, Sergei; Karasik, Boris S.; Kawamura, Jonathan H.; McGrath, William R.; Sergeev, Andrei V.; Gershenson, Michael E.

    2006-01-01

    We are developing a hot-electron superconducting transition-edge sensor (TES) that is capable of counting THz photons and operates at T = 0.3K. The main driver for this work is moderate resolution spectroscopy (R approx. 1000) on the future space telescopes with cryogenically cooled (approx. 4 K) mirrors. The detectors for these telescopes must be background-limited with a noise equivalent power (NEP) approx. 10(exp -19)-10(exp -20) W/Hz(sup 1/2) over the range v = 0.3-10 THz. Above about 1 THz, the background photon arrival rate is expected to be approx. 10-100/s), and photon counting detectors may be preferable to an integrating type. We fabricated superconducting Ti nanosensors with a volume of approx. 3x10(exp -3) cubic microns on planar substrate and have measured the thermal conductance G to the thermal bath. A very low G = 4x10(exp -14) W/K, measured at 0.3 K, is due to the weak electron-phonon coupling in the material and the thermal isolation provided by superconducting Nb contacts. This low G corresponds to NEP(0.3K) = 3x10(exp -19) W/Hz(sup 1/2). This Hot-Electron Direct Detector (HEDD) is expected to have a sufficient energy resolution for detecting individual photons with v > 0.3 THz at 0.3 K. With the sensor time constant of a few microseconds, the dynamic range is approx. 50 dB.

  12. Superconductivity from magnetic elements under high pressure

    International Nuclear Information System (INIS)

    Shimizu, Katsuya; Amaya, Kiichi; Suzuki, Naoshi; Onuki, Yoshichika

    2006-01-01

    Can we expect the appearance of superconductivity from magnetic elements? In general, superconductivity occurs in nonmagnetic metal at low temperature and magnetic impurities destroy superconductivity; magnetism and superconductivity are as incompatible as oil and water. Here, we present our experimental example of superconducting elements, iron and oxygen. They are magnetic at ambient pressure, however, they become nonmagnetic under high pressure, then superconductor at low temperature. What is the driving force of the superconductivity? Our understanding in the early stages was a simple scenario that the superconductive state was obtained as a consequence of an emergence of the nonmagnetic states. In both cases, we may consider another scenario for the appearance of superconductivity; the magnetic fluctuation mechanism in the same way as unconventional superconductors

  13. Analysis of mechanical characteristics of superconducting field coil for 17 MW class high temperature superconducting synchronous motor

    International Nuclear Information System (INIS)

    Kim, J. H.; Park, S. I.; Im, S. H.; Kim, H. M.

    2013-01-01

    Superconducting field coils using a high-temperature superconducting (HTS) wires with high current density generate high magnetic field of 2 to 5 [T] and electromagnetic force (Lorentz force) acting on the superconducting field coils also become a very strong from the point of view of a mechanical characteristics. Because mechanical stress caused by these powerful electromagnetic force is one of the factors which worsens the critical current performance and structural characteristics of HTS wire, the mechanical stress analysis should be performed when designing the superconducting field coils. In this paper, as part of structural design of superconducting field coils for 17 MW class superconducting ship propulsion motor, mechanical stress acting on the superconducting field coils was analyzed and structural safety was also determined by the coupling analysis system that is consists of commercial electromagnetic field analysis program and structural analysis program.

  14. Superconducted tour

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1988-09-15

    Superconductivity - the dramatic drop in electrical resistance in certain materials at very low temperatures - has grown rapidly in importance over the past two or three decades to become a key technology for high energy particle accelerators. It was in this setting that a hundred students and 15 lecturers met in Hamburg in June for a week's course on superconductivity in particle accelerators, organized by the CERN Accelerator School and the nearby DESY Laboratory.

  15. Superconductivity: Phenomenology

    International Nuclear Information System (INIS)

    Falicov, L.M.

    1988-08-01

    This document discusses first the following topics: (a) The superconducting transition temperature; (b) Zero resistivity; (c) The Meissner effect; (d) The isotope effect; (e) Microwave and optical properties; and (f) The superconducting energy gap. Part II of this document investigates the Ginzburg-Landau equations by discussing: (a) The coherence length; (b) The penetration depth; (c) Flux quantization; (d) Magnetic-field dependence of the energy gap; (e) Quantum interference phenomena; and (f) The Josephson effect

  16. Array Phase Shifters: Theory and Technology

    Science.gov (United States)

    Romanofsky, Robert R.

    2007-01-01

    While there are a myriad of applications for microwave phase shifters in instrumentation and metrology, power combining, amplifier linearization, and so on, the most prevalent use is in scanning phased-array antennas. And while this market continues to be dominated by military radar and tracking platforms, many commercial applications have emerged in the past decade or so. These new and potential applications span low-Earth-orbit (LEO) communications satellite constellations and collision warning radar, an aspect of the Intelligent Vehicle Highway System or Automated Highway System. In any case, the phase shifters represent a considerable portion of the overall antenna cost, with some estimates approaching 40 percent for receive arrays. Ferrite phase shifters continue to be the workhorse in military-phased arrays, and while there have been advances in thin film ferrite devices, the review of this device technology in the previous edition of this book is still highly relevant. This chapter will focus on three types of phase shifters that have matured in the past decade: GaAs MESFET monolithic microwave integrated circuit (MMIC), micro-electromechanical systems (MEMS), and thin film ferroelectric-based devices. A brief review of some novel devices including thin film ferrite phase shifters and superconducting switches for phase shifter applications will be provided. Finally, the effects of modulo 2 phase shift limitations, phase errors, and transient response on bit error rate degradation will be considered.

  17. Introduction to superconductivity

    CERN Document Server

    Darriulat, Pierre

    1998-01-01

    The lecture series will address physicists, such as particle and nuclear physicists, familiar with non-relativistic quantum mechanics but not with solid state physics. The aim of this introduction to low temperature superconductivity is to give sufficient bases to the student for him/her to be able to access the scientific literature on this field. The five lectures will cover the following topics : 1. Normal metals, free electron gas, chambers equation. 2. Cooper pairs, the BCS ground state, quasi particle excitations. 3. DC superconductivity, Meissner state, dirty superconductors.4. Self consistent approach, Ginsburg Landau equations, Abrikosov fluxon lattice. 5. Josephson effects, high temperature superconductivity.

  18. Calorimetric cryodetectors for heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Egelhof, P; Henning, W; Kienlin, A v; Meier, J; Truebenbacher, V [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany, F.R.) Mainz Univ. (Germany, F.R.). Inst. fuer Physik; Azgui, F [CDTN, Algiers (Algeria); Shepard, K [Argonne National Lab., IL (USA)

    1990-01-01

    Status and first test results are reported for a project to develop calorimetric cryodetectors for heavy ions. The special conditions for the detection of energetic heavy ions are discussed. Presently the investigations are focussed on semiconductor bolometers and aluminium-strip superconducting phase-transition thermometers that are cooled with liquid {sup 4}He and operate in the temperature range 1.3-4.2 K. For a germanium bolometer the temperature dependence of the resistance, voltage-current curves, the time response to heating by voltage pulses and the response to ionizing {alpha}-radiation are reported. First tests on phase transition thermometers using thin aluminum strips yield a transition width of {Delta}T=8.6 mK at T{sub c}=1.467 K. (orig.).

  19. The Atacama Cosmology Telescope: Instrument

    Science.gov (United States)

    Thornton, Robert J.; Atacama Cosmology Telescope Team

    2010-01-01

    The 6-meter Atacama Cosmology Telescope (ACT) is making detailed maps of the Cosmic Microwave Background at Cerro Toco in northern Chile. In this talk, I focus on the design and operation of the telescope and its commissioning instrument, the Millimeter Bolometer Array Camera. The camera contains three independent sets of optics that operate at 148 GHz, 217 GHz, and 277 GHz with arcminute resolution, each of which couples to a 1024-element array of Transition Edge Sensor (TES) bolometers. I will report on the camera performance, including the beam patterns, optical efficiencies, and detector sensitivities. Under development for ACT is a new polarimeter based on feedhorn-coupled TES devices that have improved sensitivity and are planned to operate at 0.1 K.

  20. The development of superconducting equipment

    CERN Document Server

    Ueda, T; Hiue, H

    2003-01-01

    Fuji Electric has been developing various types of superconducting equipment for over a quarter of a century. This paper describes the development results achieved for superconducting equipment and especially focuses on large-capacity current leads and superconducting transmission systems, the development of which is being promoted for application to the field of nuclear fusion. High temperature superconductor (HTS) is becoming the mainstream in the field of superconductivity, and the HTS floating coil and conduction-cooled HTS transformed are also introduced as recent developments for devices that utilize this technology. (author)