Sökning: "topological"

Visar resultat 1 - 5 av 265 avhandlingar innehållade ordet topological.

  1. 1. Topological Combinatorics

    Författare :Alexander Engström; Svante Linusson; Günter M. Ziegler; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; MATHEMATICS; MATEMATIK;

    Sammanfattning : This thesis on Topological Combinatorics contains 7 papers. All of them but paper Bare published before.In paper A we prove that!i dim ˜Hi(Ind(G);Q) ! |Ind(G[D])| for any graph G andits independence complex Ind(G), under the condition that G\D is a forest. LÄS MER

  3. 2. Solvable Topological Boundaries

    Författare :Flore Kiki Kunst; Emil Bergholtz; Henning Schomerus; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; teoretisk fysik; Theoretical Physics;

    Sammanfattning : The hallmark of topological phases of matter is the presence of robust boundary states. In this dissertation, a formalism is developed with which analytical solutions for these states can be straightforwardly obtained by making use of destructive interference, which is naturally present in a large family of lattice models. LÄS MER

  4. 3. Consequences of a non-trivial band-structure topology in solids : Investigations of topological surface and interface states

    Författare :Magnus H. Berntsen; Oscar Tjernberg; Philip Hofmann; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; spin- and angle-resolved photoelectron spectroscopy; time-of-flight analyzer; laser based light source; topological insulator; topological crystalline insulator; thin films; surface state; interface state; Bi2Se3; Pb1-xSnxSe;

    Sammanfattning : The development and characterization of experimental setups for angle-resolved photoelectron spectroscopy (ARPES) and spin- and angle-resolved photoelectron spectroscopy (SARPES) is described. Subsequently, the two techniques are applied to studies of the electronic band structure in topologically non-trivial materials. LÄS MER

  5. 4. Topological superconductivity in multiorbital materials

    Författare :Johann Schmidt; Annica M. Black-Schaffer; Karyn Le Hur; Uppsala universitet; []
    Nyckelord :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

  7. 5. Topological Phase Transitions in Magnetic Nanostructures of Dirac Materials

    Författare :Nezhat Pournaghavi; Carlo M. Canali; Michael Flatté; Linnéuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Topological insulators; Magnetic materials; Quantum anomalous Hall effect; Topological magneto electric effect; Dirac semimetals; Weyl semimetals; Condensed Matter Physics; Kondenserade materians fysik;

    Sammanfattning : Over the past two decades, the discovery of topological Dirac materials, such as topological insulators and semimetals, has defined a new paradigm in condensed matter physics and established new platforms for realizing spin electronic devices and quantum computing. The novel quantum properties of these materials, which are mainly due to the presence of strong spin-orbit coupling, are invariant under topological transformations, making them more resilient to structural disorder, electromagnetic and thermal fluctuations in comparison to the conventional silicon-based materials. LÄS MER