Sökning: "quasiclassical theory"

Hittade 4 avhandlingar innehållade orden quasiclassical theory.

  1. 1. Mesoscopic superconductivity quasiclassical approach

    Detta är en avhandling från Umeå : Umeå universitet

    Författare :Marek Ožana; Umeå universitet.; [2001]
    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

  2. 2. Crystallization of the superconducting phase in unconventional superconductors

    Detta är en avhandling från ; Chalmers tekniska högskola; Gothenburg

    Författare :Patric Holmvall; [2019]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; pattern formation; spontaneous symmetry breaking; Andreev bound states; mesoscopic superconductivity; phase crystals; thin superconducting films; phase transitions; non-local Ginzburg-Landau theory; time-reversal symmetry; flat bands; unconventional superconductivity; quasiclassical theory; translational symmetry; cuprates; inhomogeneous superconductivity;

    Sammanfattning : Superconductivity is a macroscopic quantum phenomenon, in the sense that a macroscopic number of electrons form a pair condensate, that occupies a single ground state. The electrons in this state are phase-coherent, breaking global U (1)-symmetry, and spatial variations of the phase imply superflows that usually cost kinetic energy, resulting in a uniform and rigid phase. LÄS MER

  3. 3. Mesoscopic thin film superconductors - A computational framework

    Detta är en avhandling från ; Chalmers tekniska högskola; Gothenburg

    Författare :Mikael Håkansson; [2015]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Riccati equation; quasiclassical theory; simulation; GPU; time-reversal symmetry; CUDA; Eilenberger equation; coherence functions; Superconductivity; computational;

    Sammanfattning : Motivated by experiments on superconductors in the microscopic regime and the realization of small superconducting devices such as qubits, we initiate a computational project in the form of a numerical simulation package to model and predict the behavior of these type of systems. It is a multidisciplinary endeavor in that it employs theory, computational science, software design, and to some extent new visualization techniques. LÄS MER

  4. 4. Modeling mesoscopic unconventional superconductors

    Detta är en avhandling från ; Chalmers tekniska högskola; Gothenburg

    Författare :Patric Holmvall; [2017]
    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