Sökning: "magnetization"

Visar resultat 1 - 5 av 158 avhandlingar innehållade ordet magnetization.

  1. 1. Ultrafast Magnetization Dynamics : Element-selective studies of magnetic alloys using ultra short XUV pulses

    Författare :Rameez Saeed Malik; Olof Karis; Uwe Bovensiepen; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magnetization dynamics; magnetic alloys; HHG; ultrashort laser pulses; magneto-optical Kerr effect MOKE ; Gilbert damping; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : In this thesis, I investigate the ultrafast magnetization dynamics in 3d ferromagnets and their alloys with ultrashort laser pulses. The high harmonics generation (HHG) setup provides extreme-ultraviolet photons with energies 35-72 eV, which is the energy range where 3d metals have their M2,3 absorption edges. LÄS MER

  3. 2. Magnetization Dynamics in Ferromagnetic Thin Films : Evaluation of Different Contributions to Damping in Co2FeAl and FeCo Film Structures

    Författare :Serkan Akansel; Peter Svedlindh; Olof Karis; Erik Wahlström; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spintronics; Gilbert damping parameter; magnetization dynamics; ferromagnetic resonance; Heusler alloys; magnetic thin films; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : Static and dynamic magnetic properties of Co2FeAl and Fe65Co35 alloys have been investigated. Co2FeAl films were deposited at different temperatures and the deposition parameters were optimized with respect to structural and magnetic properties. As a result, a film with B2 crystalline phase was obtained without any post-annealing process. LÄS MER

  4. 3. Electromagnetic Modelling of Power Transformers with DC Magnetization

    Författare :Seyed Ali Mousavi; Göran Engdahl; S. V. Kulkarni; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Transformer; Hysteresis; DC magnetization; GICs; FEM; reluctance network method;

    Sammanfattning : DC currents that flow through the ground can be injected to the star windings of power transformers from their grounded neutral points and close their path with transmission lines. The geomagnetically induced currents (GICs) and AC/DC convertors of high voltage direct current (HVDC) systems are the sources of such DC currents. LÄS MER

  5. 4. Magnetization Dynamics in Nano-Contact Spin Torque Oscillators : Solitonic bullets and propagating spin waves

    Författare :Stefano Bonetti; Johan Åkerman; Thomas Silva; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magnetism; spintronics; thin magnetic films; spin transfer torque; magnetization dynamics; spin waves; microwave oscillators; giant magneto-resistance; Magnetism; Magnetism;

    Sammanfattning : Magnetization dynamics in nano-contact spin torque oscillators (STOs) is investigated from an experimental and theoretical point of view. The fundamentals of magnetization dynamics due to spin transfer torque are given. A custom-made high frequency (up to 46 GHz) in large magnetic fields (up to 2. LÄS MER

  7. 5. 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