Sökning: "Superconductor"

Visar resultat 6 - 10 av 118 avhandlingar innehållade ordet Superconductor.

  1. 6. Superradiant THz wave emission from arrays of Josephson junctions

    Författare :Ievgenii Borodianskyi; Vladimir Krasnov; Yury Shukrinov; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Josephson junction; Superconductor; ThZ emission; high-Tc; Physics; fysik;

    Sammanfattning : High-power, continuous-wave, compact and tunable THz sources are needed for a large variety of applications. Development of power-efficient sources of electromagnetic radiation in the 0.1-10 THz range is a difficult technological problem, known as the “THz gap. LÄS MER

  3. 7. Magnesium Diboride (MgB2) and Ca-doped YBa2Cu3O7-? : Thin Films and Devices. Fabrication and Characterization

    Författare :Anayesu Malisa; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ca-doped YBa2Cu3O7-?; MgB2; bicrystal; superconductor; nanobridge; thin film; Josephson effect; Josephson junction;

    Sammanfattning : Magnesium diboride (MgB2) is a superconductor with an exceptionally high transition temperature, Tc, of 39 K. This work describes deposition of high quality and superconducting films of MgB2 for electronic applications. Experiments on Ca-doped YBa2Cu3O7-? films and fabrication of bicrystal Josephson junctions are also described. LÄS MER

  4. 8. Interacting Dirac Matter

    Författare :Saikat Banerjee; Alexander V. Balatsky; Jens Paaske; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Dirac; superconductor; magnon; interaction; Fermi liquid theory; renormalization; Fysik; Physics;

    Sammanfattning : The discovery of graphene in 2004 has led to a surge of activities focused on the theoretical and experimental studies of materials hosting linearly dispersive quasiparticles during the last decade. Rapid expansion in the list of materials having similar properties to graphene has led to the emergence of a new class of materials known as the Dirac materials. LÄS MER

  5. 9. Device Technology Based on High Temperature Superconductors and Microwave Breakdown in Gases

    Författare :Martin Löfgren; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; distortion; penetration depth; surface resistance; transmit-receive switch; coupled-grain model; high-power; microwave; pulse; surface impedance; breakdown; propagation; modulator; air; superconductor; transmission line; resonator; coplanar waveguide; plasma;

    Sammanfattning : This thesis deals with two separate fields of microwave technology. The first section treats microwave characterization and applications of high temperature superconducting (HTS) thin films, while the second section treats microwave breakdown in transmit-receive (TR) switches and in air. Within the first section, four main topics are adressed. LÄS MER

  7. 10. Characteristic properties of two-dimensional superconductors close to the phase transition in zero magnetic field

    Författare :Kateryna Medvedyeva; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik; superconductor; two dimensions; phase transition; vortex; currentvoltage characteristics; complex conductivity; scaling; critical exponents; XY-type models; dynamics; Physics; Fysik; fysik; Physics;

    Sammanfattning : The main focus of this thesis lies on the critical properties of twodimensional (2D) superconductors in zero magnetic field. Simulations based on variants of the 2D XY model are shown to give characteristic features close to the phase transition which agree qualitatively with experimental data. LÄS MER