Sökning: "sis"

Visar resultat 1 - 5 av 94 avhandlingar innehållade ordet sis.

  1. 1. Development of Cryogenic Low Noise 4-8 GHz HEMT Amplifier and its Advanced Characterization

    Författare :Erik Sundin; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; shot-noise; low noise amplifier; cryogenic amplifier; sis; noise measurement; HEMT;

    Sammanfattning : In most radio astronomy instrumentation, cryogenic low noise amplifiers (LNA) are used as intermediate frequency (IF) amplifiers. The system noise temperature is among the most important parameters of a receiver and requires state of the art components. LÄS MER

  3. 2. Growth and Characterization of Nb3Al Thin Films for Low-Noise Terahertz Electronics

    Författare :Dimitar Milkov Dochev; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; tunnel junction; SIS; Nb3Al; hot electron bolometer; thin film; superconductor; epitaxial film; magnetron co-sputtering;

    Sammanfattning : Demand on ultimately sensitive heterodyne receivers for, e.g., radio astronomy and environmental science instrumentation, has driven large research activities on novel materials and devices for extending the frequency range into the THz domain. LÄS MER

  4. 3. Thin Films and Component Technologies for Low-Noise Terahertz Electronics

    Författare :Dimitar Milkov Dochev; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; THz electronics; SIS; tunnel junctions; Nb3Al; NbN; thin film; hot electron bolometer; microwave circuits; superconductor; epitaxial film;

    Sammanfattning : This thesis deals with several distinct subjects such as thin film deposition, design, fabrication and characterization of components for low-noise THz electronics.High energy-gap superconducting materials are of specific importance for low-noise THz mixer applications. LÄS MER

  5. 4. Antenna Integrated Superconducting Mixers

    Författare :Hans Ekström; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; tapered slotline antenna; mixer; double dipole antenna; superconducting; hot electron; receiver; Niobium; bolometer; trilayer junction; edge junction; Niobium Nitride; SIS;

    Sammanfattning : This thesis investigates the prospects of some different superconducting mixers integrated with planar antennas for the millimeter and submillimeter regime. Two kinds of Superconductor/Insulator/Superconductor (SIS) tunnel junctions for use in mixers have been fabricated; Nb/PbBi edge junctions and Nb trilayer junctions. LÄS MER

  7. 5. Two components for an imaging receiver

    Författare :Guillermo F. Delgado Gunckel; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; broadband waveguide probe; Quasi-optical; SIS; finite elements; nipi MQW; opto-electronic modulator; fourier transform spectrometer; scale model;

    Sammanfattning : .... LÄS MER