Sökning: "Landau damping"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden Landau damping.

  1. 1. Higher harmonic cavities at 3rd generation synchrotron light sources

    Författare :Mattias Georgsson; Lunds universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Double RF system; Electron storage ring; Instabilities; Landau damping; Beam lifetime; Physics; Synchrotron radiation; Fysik;

    Sammanfattning : Synchrotron radiation is a tool widely used in science. It is produced by electron accelerators called storage rings. With the high performance of the 3rd generation synchrotron light sources, the scientific results are excellent. It is important to identify and overcome the limitations of a storage ring in order to enhance its performance. LÄS MER

  3. 2. Relativistic theory of laser-induced magnetization dynamics

    Författare :Ritwik Mondal; Peter M. Oppeneer; Jan Rusz; Olle Eriksson; Paul-Antoine Hervieux; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Relativistic quantum electrodynamics; magneto-optics; spin-orbit coupling; ultrafast demagnetization; inverse Faraday effect; magnetic inertia; Gilbert damping; Fysik; Physics;

    Sammanfattning : Ultrafast dynamical processes in magnetic systems have become the subject of intense research during the last two decades, initiated by the pioneering discovery of femtosecond laser-induced demagnetization in nickel. In this thesis, we develop theory for fast and ultrafast magnetization dynamics. LÄS MER

  4. 3. Ferromagnetic Resonance as a Probe of Magnetization Dynamics : A Study of FeCo Thin Films and Trilayers

    Författare :Yajun Wei; Peter Svedlindh; Sujeet Chaudhary; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ferromagnetic resonance FMR ; Gilbert damping; magnetic coupling; FeCo;

    Sammanfattning : The high frequency dynamic magnetic responses of FeCo thin films and structures have been investigated mainly using ferromagnetic resonance (FMR) technique.The FMR resonance condition and linewidth are first derived from the dynamic Landau- Lifshitz-Gilbert equation, followed by a study of the conversion between FMR field and frequency linewidths. LÄS MER

  5. 4. Analysis and numerical methods for multiscale problems in magnetization dynamics

    Författare :Lena Leitenmaier; Olof Runborg; Carlos Garcia-Cervera; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Numerical Analysis; Numerisk analys;

    Sammanfattning : This thesis investigates a multiscale version of the Landau-Lifshitz equation and how to solve it using the framework of Heterogeneous Multiscale Methods (HMM). The Landau-Lifshitz equation is the governing equation in micromagnetics, modeling magnetization dynamics. LÄS MER

  7. 5. Quantum Kinetic Theory for Plasmas : spin, exchange, and particle dispersive effects

    Författare :Robin Ekman; Gert Brodin; Jens Zamanian; Bengt Eliasson; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; teoretisk fysik; Theoretical Physics;

    Sammanfattning : This thesis is about developing and studying quantum mechanical models of plasmas. Quantum effects can be important at high densities, at low temperatures, and in strong electromagnetic fields, in various laboratory and astrophysical systems. LÄS MER