Sökning: "unconventional superconductivity"

Visar resultat 1 - 5 av 21 avhandlingar innehållade orden unconventional superconductivity.

  1. 1. Selfconsistent theory of superconductivity in unconventional superconductors

    Författare :Fabian Schrodi; Peter M. Oppeneer; Alex Aperis; Jörg Schmalian; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; superconductivity; unconventional; Eliashberg theory;

    Sammanfattning : Superconductivity is broadly believed to stem from either electron-phonon interaction (EPI) or from purely electronic mechanisms, such as antiferromagnetic spin fluctuations. For many materials the discussion about which of these interactions is the dominant "pairing glue" is still ongoing. 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 :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. 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

  4. 4. 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. 5. Nanocalorimetry of electronic phase transitions in systems with unconventional superconductivity and magnetic ordering

    Författare :Donato Campanini; Andreas Rydh; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nanocalorimetry; Superconductivity; Magnetism; Electronic phase transitions; Physics Of Matter; materiefysik; fysik; Physics;

    Sammanfattning : In this thesis, low temperature specific heat measurements on small (μg) single crystals of different superconducting and magnetic systems are presented. The device used in this work features a combination of high sensitivity and good accuracy over the temperature range 1-400 K and allows measurements in high magnetic fields. LÄS MER