Sökning: "Non-collinear magnetism"

Visar resultat 1 - 5 av 13 avhandlingar innehållade orden Non-collinear magnetism.

  1. 1. Non-collinear Magnetism in d- and f-electron Systems

    Författare :Raquel Lizárraga Jurado; Olle Eriksson; Lars Nordström; Axel Svane; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Non-collinear magnetism; spin spirals; first principles; density functional theory; Fermi surfaces; electronic structure; f-electron systems; Fysik;

    Sammanfattning : In this thesis, non-collinear magnetism has been studied by using density functional theory and the augmented plane wave method with local orbitals (APW+lo). Two conditions for non-collinear instabilities have been identified in this thesis. First, the Fermi energy should cut through both spin up and down states. LÄS MER

  3. 2. A Theoretical Study of Magnetism in Nanostructured Materials

    Författare :Anders Bergman; Olle Eriksson; Lars Nordström; Hugues Dreysse; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; magnetism; clusters; non-collinear; multilayers; first-principles theory; electronic structure; high-moment materials; exchange interactions; linear scaling methods; Fysik;

    Sammanfattning : A first-principles linear scaling real-space method for investigating non-collinear magnetic behaviour of nanostructured materials has been developed. With this method, the magnetic structures of small supported transition metal clusters have been examined. LÄS MER

  4. 3. Augmented Planewaves, Developments and Applications to Magnetism

    Författare :Elisabeth Sjöstedt; Ruqian Wu; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; First principles electronic structure calculations; augmented planewaves; non-collinear magnetism; in-plane magnetic anisortopy; hyperfine parameters; Fysik; Physics; Fysik; fysik; Physics;

    Sammanfattning : The present thesis concerns method development and applications in the field of first principles electronic structure calculations.Augmented planewaves combine the simple planewaves with exact solutions of the Schrödinger equation for a spherical potential. LÄS MER

  5. 4. Trends in Magnetism : From Strong Correlations to “-onics” Technology

    Författare :Dmitry Yudin; Olle Eriksson; Grigori Volovik; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Strongly interacting electron systems; Spin dynamics; Topological matter; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : Despite of enormous progress in experimental nanophysics theoretical studies of low-dimensional electron systems still remains a challenging task. Indeed, most of the structures are strongly correlated, so that an effective perturbative treatment is impossible due to the lack of a small parameter. LÄS MER

  7. 5. Electronic structure and exchange interactions from ab initio theory : New perspectives and implementations

    Författare :Ramon Cardias Alves de Almeida; Olle Eriksson; Anders Bergman; Attila Szilva; R. B. Muniz; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ab initio; exchange interactions; non-collinear magnetism; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : In this thesis, the magnetic properties of several materials were investigated using first principle calculations. The ab initio method named real space linear muffin-tin orbitals atomic sphere approximation (RS-LMTO-ASA) was used to calculate the electronic structure and magnetic properties of bulk systems, surface and nanostructures adsorbed on surfaces. LÄS MER