206 research outputs found

    Infrared receivers for low background astronomy: Incoherent detectors and coherent devices from one micrometer to one millimeter

    Get PDF
    The status of incoherent detectors and coherent receivers over the infrared wavelength range from one micrometer to one millimeter is described. General principles of infrared receivers are included, and photon detectors, bolometers, coherent receivers, and important supporting technologies are discussed, with emphasis on their suitability for low background astronomical applications. Broad recommendations are presented and specific opportunities are identified for development of improved devices

    Field Measurements

    Get PDF
    The measurement of the magnetic field is often the final verification of the complex design and fabrication process of a magnetic system. In several cases, when seeking high accuracy, the measurement technique and its realization can result in a considerable effort. This note describes most used measurement techniques, such as nuclear magnetic resonance, fluxmeters and Hall generators, and their typical range of application. In addition some of less commonly used techniques, such as magneto-optical, SQUIDs, or particle beams methods, are listed

    NASA Thesaurus supplement: A four part cumulative supplement to the 1988 edition of the NASA Thesaurus (supplement 3)

    Get PDF
    The four-part cumulative supplement to the 1988 edition of the NASA Thesaurus includes the Hierarchical Listing (Part 1), Access Vocabulary (Part 2), Definitions (Part 3), and Changes (Part 4). The semiannual supplement gives complete hierarchies and accepted upper/lowercase forms for new terms

    Defect-based testing of LTS digital circuits

    Get PDF
    A Defect-Based Test (DBT) methodology for Superconductor Electronics (SCE) is presented in this thesis, so that commercial production and efficient testing of systems can be implemented in this technology in the future. In the first chapter, the features and prospects for SCE have been presented. The motivation for this research and the outline of the thesis were also described in Chapter 1. It has been shown that high-end applications such as Software-Defined Radio (SDR) and petaflop computers which are extremely difficult to implement in top-of-the-art semiconductor technologies can be realised using SCE. But, a systematic structural test methodology had yet to be developed for SCE and has been addressed in this thesis. A detailed introduction to Rapid Single-Flux Quantum (RSFQ) circuits was presented in Chapter 2. A Josephson Junction (JJ) was described with associated theory behind its operation. The JJ model used in the simulator used in this research work was also presented. RSFQ logic with logic protocols as well as the design and implementation of an example D-type flip-flop (DFF) was also introduced. Finally, advantages and disadvantages of RSFQ circuits have been discussed with focus on the latest developments in the field. Various techniques for testing RSFQ circuits were discussed in Chapter 3. A Process Defect Monitor (PDM) approach was presented for fabrication process analysis. The presented defect-monitor structures were used to gather measurement data, to find the probability of the occurrence of defects in the process which forms the first step for Inductive Fault Analysis (IFA). Results from measurements on these structures were used to create a database for defects. This information can be used as input for performing IFA. "Defect-sprinkling" over a fault-free circuit can be carried out according to the measured defect densities over various layers. After layout extraction and extensive fault simulation, the resulting information will indicate realistic faults. In addition, possible Design-for-Testability (DfT) schemes for monitoring Single-Flux Quantum (SFQ) pulses within an RSFQ circuit has also been discussed in Chapter 3. The requirement for a DfT scheme is inevitable for RSFQ circuits because of their very high frequency of operation and very low operating temperature. It was demonstrated how SFQ pulses can be monitored at an internal node of an SCE circuit, introducing observability using Test-Point Insertion (TPI). Various techniques were discussed for the introduction of DfT and to avoid the delay introduced by the DfT structure if it is required. The available features in the proposed design for customising the detector make it attractive for a detailed DBT of RSFQ circuits. The control of internal nodes has also been illustrated using TPI. The test structures that were designed and implemented to determine the occurrence of defects in the processes can also be used to locate the position for the insertion of the above mentioned DfT structures

    Superconductors at the Nanoscale

    Get PDF
    By covering theory, design, and fabrication of nanostructured superconducting materials, this monograph is an invaluable resource for research and development. Examples are energy saving solutions, healthcare, and communication technologies. Key ingredients are nanopatterned materials which help to improve the superconducting critical parameters and performance of superconducting devices, and lead to novel functionalities. Contents Tutorial on nanostructured superconductors Imaging vortices in superconductors: from the atomic scale to macroscopic distances Probing vortex dynamics on a single vortex level by scanning ac-susceptibility microscopy STM studies of vortex cores in strongly confined nanoscale superconductors Type-1.5 superconductivity Direct visualization of vortex patterns in superconductors with competing vortex-vortex interactions Vortex dynamics in nanofabricated chemical solution deposition high-temperature superconducting films Artificial pinning sites and their applications Vortices at microwave frequencies Physics and operation of superconducting single-photon devices Josephson and charging effect in mesoscopic superconducting devices NanoSQUIDs: Basics & recent advances intrinsic Josephson junction stacks as emitters of terahertz radiation| Interference phenomena in superconductor-ferromagnet hybrids Spin-orbit interactions, spin currents, and magnetization dynamics in superconductor/ferromagnet hybrids Superconductor/ferromagnet hybrid

    Spaceborne sensors (1983-2000 AD): A forecast of technology

    Get PDF
    A technical review and forecast of space technology as it applies to spaceborne sensors for future NASA missions is presented. A format for categorization of sensor systems covering the entire electromagnetic spectrum, including particles and fields is developed. Major generic sensor systems are related to their subsystems, components, and to basic research and development. General supporting technologies such as cryogenics, optical design, and data processing electronics are addressed where appropriate. The dependence of many classes of instruments on common components, basic R&D and support technologies is also illustrated. A forecast of important system designs and instrument and component performance parameters is provided for the 1983-2000 AD time frame. Some insight into the scientific and applications capabilities and goals of the sensor systems is also given

    Back-end Design of the Readout System for Cryogenic Particle Detectors

    Get PDF
    Diese Arbeit widmet sich dem Design und der Entwicklung des digitalen Back-Ends (D-BE) für Raumtemperatur-Ausleseelektronik, die in kryogenen Quantendetektoren verwendet wird. Der Schwerpunkt liegt auf Anwendungen im Zusammenhang mit Experimenten zur Kosmischen Hintergrundstrahlung (CMB, im Englischen \textit{Cosmic Microwave Background radiation} genannt), jedoch ist die Technologie anpassbar für Partikeldetektionsexperimente. Zwei Schlüsselprojekte stehen im Mittelpunkt dieser Forschung: das QUBIC-Projekt zur Erkennung der B-Mode-Polarisation des CMB und das ECHo-Experiment, das darauf abzielt, eine neue Obergrenze für die Bestimmung der Neutrinomasse im Sub-eV-Bereich festzulegen. In diesen Projekten werden Übergangskanten-Sensoren (TES) und magnetische Mikrokalorimeter (MMCs) eingesetzt. Im Fall des QUBIC-Projekts werden die TES unter Verwendung von Zeitaufteilungsmultiplexing (TDM) gemultiplext. Es wurde jedoch ein Vorschlag für einen neuen Bolo\-meter-Typ namens Magnetischer Mikrobolometer (MMB) in der QUBIC-Kollaboration vorgestellt, der die Implementierung eines Frequenzaufteilungsmultiplexing (FDM)-Sys\-tems ermöglicht. Dies könnte durch die Verwendung eines Mikrowellen-Supraleiter-Quan\-teninterferenzgerät (SQUID)-Multiplexers (μ\muMUX) erreicht werden, ähnlich wie bei den MMCs im ECHo-Experiment. Zur Erleichterung der Auslese der gemultiplexten Detektoren wird ein mehrtoniges Signal erzeugt, wobei jede Frequenztonkomponente einen μ\muMUX-Kanal innerhalb des Kryostaten überwacht. Dieses Signal passiert dann einen rauscharmen Verstärker (LNA, im Englischen \textit{Low-Noise Amplifier} genannt), der in der Regel in der 4 K-Stufe liegt, bevor es das Hochfrequenz-Front-End (RF-FE) erreicht. Das RF-FE umfasst Hochfrequenzelektronik, die sowohl mit dem D-BE als auch mit der Elektronik im Kryostaten verbunden ist. Diese Arbeit stellt eine neuartige Anwendung des Goertzel-Filters zur Kanalisierung von mehrtonigen Signalen vor. Durch Simulationen, die mit einem in dieser Arbeit entwickelten auf Python basierenden Softwarepaket durchgeführt wurden, wurde die optimale Konfiguration für die Signalgenerierung und -erfassung in Bezug auf Rauschleistung, Abschirmung gegen Übersprechen und Systemlinearität ermittelt. Diese Arbeit zeigt, wie dieser Ansatz effizient in einem Field Programmable Gate Array (FPGA) implementiert werden kann, was die Skalierbarkeit bei der Auslese mehrerer Sensoren ermöglicht. Diese Skalierung is im Besonderen in Anwendungen wie Radioteleskopen für CMB-Messungen, kryogenen Kalorimetern für die Partikeldetektion und Quantencomputing entscheidend. Umfangreiche Validierungsexperimente zeigen, wie die Implementierung dieses Filtersatzes die Kanalisierung des mehrtonigen Eingangssignals zur Wiederherstellung der von den Detektoren aufgezeichneten Daten ermöglicht
    • …
    corecore