Sökning: "atomistic spin dynamics"

Visar resultat 1 - 5 av 15 avhandlingar innehållade orden atomistic spin dynamics.

  1. 1. Atomistic Spin Dynamics, Theory and Applications

    Författare :Johan Hellsvik; Olle Eriksson; Lars Nordström; Ulrich Nowak; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ab initio calculations; spin dynamics; magnetization; magnetic switching; diluted magnetic semiconductors; spin glasses; ferromagnetic relaxation; ferrimagnets; antiferromagnets; Magnetism; Magnetism; Condensed matter physics; Kondenserade materiens fysik; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : The topic of this Thesis is magnetization dynamics on atomic length scales. A computational scheme, Atomistic Spin Dynamics, based on density functional theory, the adiabatic approximation and the atomic moment approximation is presented. LÄS MER

  3. 2. Spin Dynamics and Magnetic Multilayers

    Författare :Björn Skubic; Olle Eriksson; Lars Nordström; Mark D. Stiles; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; magnetism; electronic structure; density functional theory; spin dynamics; spin-transfer torque; spin-density wave; multilayer; interface structure; Fysik;

    Sammanfattning : Theoretical studies based on first-principles theory are presented for a number of different magnetic systems. The first part of the thesis concerns spin dynamics and the second part concerns properties of magnetic multilayers. The theoretical treatment is based on electronic structure calculations performed by means of density functional theory. LÄS MER

  4. 3. Magnetization dynamics on the nanoscale : From first principles to atomistic spin dynamics

    Författare :Jonathan Philippe Chico Carpio; Anders Bergman; Samir Lounis; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : In this thesis first-principles methods, based on density functional theory, have been used to characterize a wide range of magnetic materials. Special emphasis has been put on pairwise magnetic interactions, such as Heisenberg exchange and Dzyaloshinskii-Moriya interactions, and also on in the Gilbert damping parameter. LÄS MER

  5. 4. Magnetization dynamics of complex magnetic materials by atomistic spin dynamics simulations

    Författare :Raghuveer Chimata; Biplab Sanyal; Olle Eriksson; Koopmans Bert; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ultrafast remagnetization; ultrafast dynamics; magnetism; multiferroics; amorphous alloys; DFT; spinels magnetostriction; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : In recent years, there has been an intense interest in understanding the microscopic mechanism of laser induced ultrafast magnetization dynamics in picosecond time scales. Magnetization switching on such a time scale has potential to be a significant boost for the data storage industry. LÄS MER

  7. 5. Spin Vortices, Interlayer Exchange, and Magnetocalorics in Multilayers

    Författare :Milton Persson; Vladislav Korenivski; David B. Haviland; Coriolan Tiusan; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Spin vortex pairs; bimerons; RKKY; finite size effects; nanostructure magnetocalorics; atomistic spin dynamics; nanocalorimetry; Spinvirvelpar; bimeron; RKKY; finita storlekseffekter; magnetkalorimetri i nanostrukturer; atomistisk spindynamik; nanokalorimetri; Material and Nano Physics; Material- och nanofysik;

    Sammanfattning : In this thesis we study strongly coupled pairs of spin vortices, in a configurationsuch that the cores attract while external fields act to pull them apart, with potential applications in magnetic random access memory (MRAM) and oscillators.Inertial decoupling of the cores has been studied and can be achieved with weak nanosecond pulses by the help of anharmonicity. LÄS MER