Sökning: "mesoscopic"

Visar resultat 1 - 5 av 108 avhandlingar innehållade ordet mesoscopic.

  1. 1. Mesoscopic superconductivity : quasiclassical approach

    Författare :Marek Ožana; Andrei Shelankov; Dierk Rainer; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; mesoscopic superconductivity; quasiclassical theory; boundary conditions; multi-layer structures; Gor kov equations; quasiclassical Green s function; Green s function on classical trajectories;

    Sammanfattning : This Thesis is concerned with the quasiclassical theory of meso-scopic superconductivity. The aim of the Thesis is to introduce the boundary conditions for a quasiclassical Green’s function on partially transparent interfaces in mesoscopic superconducting structures and to analyze the range of applicability of the quasiclassical theory. LÄS MER

  3. 2. Mechanical and Electrical Properties of Mesoscopic Wires

    Författare :Sara Blom; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Rabi oscillations; conductance quantization; free electron model; mesoscopic; microwave; channel; force fluctuations; adiabatic; nanowire;

    Sammanfattning : The mechanical and electrical properties of mesoscopic wires have been studied theoretically using a free electron model. When a mesoscopic wire is elongated the conductance decreases in steps. Each step is accompanied by an abrupt change in the force. LÄS MER

  4. 3. Modeling mesoscopic unconventional superconductors

    Författare :Patric Holmvall; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; phase transitions; Andreev bound states; quasiclassical theory; mesoscopic thin-films; spontaneous symmetry breaking; time-reversal symmetry; Unconventional superconductivity; translational symmetry;

    Sammanfattning : High-temperature superconducting materials are often experimentally realized as thin films that can be patterned into devices operating in the mesoscopic regime. On this length scale, various finite-size and surface effects heavily influence the nature of the superconducting state, and can induce new ground states with spontaneously broken symmetries. LÄS MER

  5. 4. Transport in mesoscopic superconducting devices

    Författare :Kevin Marc Seja; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; superconductivity; quasiclassical theory; mesoscopic physics; nonequilibrium superconductivity; Andreev bound states; superconducting spintronics;

    Sammanfattning : A field of growing interest within the last few decades is the study of superconductivity in mesoscopic-scale heterostructures. Mesoscopic refers to sizes between the atomic and macroscopic scales. LÄS MER

  7. 5. Fluctuations in Mesoscopic Constrictions

    Författare :Jan Peter Hessling; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; low frequency; fluctuations; quantum; noise; 1 f-noise; superconductivity; impurity; point contact; Andreev reflection; shot noise;

    Sammanfattning : In normal and superconducting quantum point contacts there are several sources of fluctuations. Thermally activated impurities in the vicinity of the junction cause the current (or voltage) to change with a typical frequency of the order of one Hz up to a few kHz. LÄS MER