Sökning: "Superconductivity"

Visar resultat 1 - 5 av 103 avhandlingar innehållade ordet Superconductivity.

  1. 1. Multicomponent superconductivity : Vortex matter and phase transitions

    Författare :Johan Carlström; Egor Babaev; Leo Radzihovsky; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; Superconductivity; Ginzburg Landau; field theory; Iron pnictide;

    Sammanfattning : The topic of this thesis is vortex-physics in multi component Ginzburg- Landau models. These models describe a newly discovered class of super- conductors with multiple superconducting gaps, and possess many properties that set them apart from single component models. LÄS MER

  2. 2. Robust Platforms for Superconductivity : Disorder Robustness and Topological Density of States Peaks

    Författare :Tomas Löthman; Annica M. Black-Schaffer; Carsten Honerkamp; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Superconductivity; Odd-Frequency Superconductivity; Nematic superconductivity; Topological Phases of Matter; Flat bands; Van Hove Singularity; Graphene; Twisted Bilayer Graphene; Rhombohedral graphite; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : We explore the connection between robust material platforms for superconductivity and the modern condensed matter physics paradigms of two-dimensional materials, topological states of matter, and odd-frequency superconductivity. Specifically, the recent discoveries of gapless topological matter and truly two-dimensional materials with graphene have greatly expanded the class of materials for which topology produces large, robust, even singular, density of states (DOS) peaks in the electronic structure that in turn are highly susceptible to new ordered states of matter, including superconductivity. LÄS MER

  3. 3. Mesoscopic superconductivity : quasiclassical approach

    Författare :Marek Ožana; Andrei Shelankov; Dierk Rainer; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; 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

  4. 4. Topological superconductivity in multiorbital materials

    Författare :Johann Schmidt; Annica M. Black-Schaffer; Karyn Le Hur; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Superconductivity; Kitaev materials; Odd-frequency superconductivity; Topological superconductivity; Fysik; Physics;

    Sammanfattning : Multiorbital materials add a new intricacy to the already complex phenomenon of superconductivity. The additional orbital degree of freedom requires leaving behind the established band picture, but also opens the possibility of more complicated order parameters with new properties. LÄS MER

  5. 5. Superconductivity in the presence of magnetic steps

    Författare :Wafaa Assaad; Matematik LTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ginzburg-Landau theory; Schrodinger operators with magnetic fields; Superconductivity; spectral theory; PDE; quantum mechanics;

    Sammanfattning : This thesis investigates the distribution of superconductivity in a Type-II planar, bounded, and smooth superconductor submitted to a piecewise-constant magnetic field with a jump discontinuity along smooth curves---the magnetic edge. This discontinuous case has not been treated before in the mathematics literature, where the considered applied magnetic field is usually assumed to be smooth. LÄS MER