Sökning: "Emil Bergholtz"

Visar resultat 1 - 5 av 11 avhandlingar innehållade orden Emil Bergholtz.

  1. 1. One-dimensional theory of the quantum Hall system

    Författare :Emil Johansson Bergholtz; Anders Karlhede; Nicholas Read; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fractional quantum Hall effect; thin torus; spin chains; conformal field theory; strong correlations; non-abelian states; Condensed matter physics; Kondenserade materiens fysik; Theoretical Physics; teoretisk fysik;

    Sammanfattning : The quantum Hall (QH) system---cold electrons in two dimensions in a perpendicular magnetic field---is a striking example of a system where unexpected phenomena emerge at low energies. The low-energy physics of this system is effectively one-dimensional due to the magnetic field. LÄS MER

  3. 2. Knotted Nodal Band Structures

    Författare :Marcus Stålhammar; Emil Bergholtz; Edwin Langmann; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; teoretisk fysik; Theoretical Physics;

    Sammanfattning : It is well known that in conventional three dimensional (3D) Hermitian two band models, the intersections between the energy bands are generically given by points. The typical example are Weyl semimetals, where these singular points can be effectively described as Weyl fermions in the low energy regime. LÄS MER

  4. 3. Topology Meets Frustration : Exact Solutions for Topological Surface States on Geometrically Frustrated Lattices

    Författare :Flore Kiki Kunst; Emil Bergholtz; Jack Lidmar; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Topology; boundary states; surface states; edge states; Chern insulator; Weyl semimetal; Theoretical Physics; teoretisk fysik;

    Sammanfattning : One of the main features of topological phases is the presence of robust boundary states that are protected by a topological invariant. Famous examples of such states are the chiral edge states of a Chern insulator, the helical edge states of a two-dimensional Z2 insulator, and the Fermi arcs of Weyl semimetals. LÄS MER

  5. 4. Geometry, Topology and Emergence in Moiré Systems

    Författare :Ahmed Abouelkomsan; Emil Johansson Bergholtz; Felix von Oppen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Moiré materials; Topological phases; Fractional Chern insulators; Quantum geometry; Quantum Hall effects; Theoretical Physics; teoretisk fysik;

    Sammanfattning : The experimental discovery of correlated insulators and superconductivity in highly tunable Van der Waals heterostructures, such as twisted bilayer graphene, has highlighted the role of moiré patterns, resulting from tiny relative twists or lattice constant mismatches, in realizing strongly correlated physics. A key ingredient is the existence of very narrow flat bands where interaction effects are dominant. LÄS MER

  7. 5. Strongly Correlated Moiré Materials

    Författare :Ahmed Abouelkomsan; Emil Bergholtz; Vladimir Juričić; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Theoretical Physics; teoretisk fysik;

    Sammanfattning : Recent advances in materials science have established Moiré materials as a new highly tunable and versatile form of quantum matter. When two dimensional atomic layers are brought into proximity, a tiny relative twist or a slight lattice mismatch produces Moiré patterns manifested in a superlattice structure with a lattice constant that is much larger than the lattice constants of the constituent layers. LÄS MER