Sökning: "spontaneous symmetry breaking"

Visar resultat 1 - 5 av 15 avhandlingar innehållade orden spontaneous symmetry breaking.

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

    Författare :Patric Holmvall; Chalmers tekniska högskola; []
    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

  2. 2. 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

  3. 3. Breaking the symmetry: creation and transfer of optical activity via total spontaneous resolution and stereoselective reactions

    Författare :Susanne Olsson; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; absolute asymmetric synthesis; enantioselective reactions; chirality; spontaneous resolution; conglomerate; organometallic chemistry; coordination compounds; attritionenhanced deracemisation; polymorphism; organolithium compounds; single-crystal X-ray crystallography;

    Sammanfattning : The generation of optical activity from achiral or racemic precursors – absolute asymmetric synthesis – is discussed in relation to the origin of biomolecular homochirality but is also often (incorrectly) regarded as being impossible. One approach to absolute asymmetric synthesis is the use of compounds that form chiral crystals. LÄS MER

  4. 4. Multi-Meson Dynamics in Chiral Perturbation Theory

    Författare :Mattias Sjö; Partikel- och kärnfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Spridningsamplituder; Effektiv Fältteori; Spontant symmetribrott; Ickelinjära sigmamodellen; Kirala Lagrangianer; Hadronspektroskopi; Strukturer och Interaktioner; Gitter-QCD; Scattering amplitudes; Effective Field Theories; Spontaneous Symmetry Breaking; Nonlinear sigma model; Chiral Lagrangians; Hadronic Spectroscopy; Structure and Interactions; Lattice QCD;

    Sammanfattning : This thesis concerns scattering of light mesons in the case where the number of external particles exceeds four (that is, three or more particles in the initial or final state), calculated using chiral perturbation theory.This is both of theoretical interest in the study of scattering amplitudes, and relevant for systems of three or more pions simulated using lattice quantum chromodynamics. LÄS MER

  5. 5. Numerical solutions to non-linear inhomogeneous problems in Superconductivity : From sphalerons to multi-band boundary states and spontaneous magnetic fields

    Författare :Andrea Ludovico Benfenati; Egor Babaev; Sedrakyan Tigran; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Teoretisk fysik; Theoretical Physics;

    Sammanfattning : This thesis is a compilation of theoretical works focused on simulating and studying open questions regarding single and multiband superconductivity. In the last decades, with the discovery of multiband superconductors, the spectrum of potential applications has greatly widened. LÄS MER