Search for dissertations about: "Spin stiffness"

Showing result 1 - 5 of 9 swedish dissertations containing the words Spin stiffness.

  2. 1. Gilbert damping of doped permalloy from first principles calculations

    Author : Fan Pan; Lars Bergqvist; Peter Svedlindh; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Gilbert damping; DFT; Permalloy; SPR-KKR; Spin stiffness; Fysik; Physics;

    Abstract : The dynamic process of how fast a spintronic device can be switched from one state to another is characterized by the Gilbert damping parameter. It has been found that the Gilbert damping along with other intrinsic properties in permalloy, can be tuned by different dopants and doping concentration. READ MORE

  4. 2. A theoretical study of magnetism and its extension to finite temperatures in random alloys

    Author : Fan Pan; Lars Bergqvist; Richard Evans; KTH; []
    Keywords : Fysik; Physics;

    Abstract : This work presents new theoretical developments of atomistic spin simulations of magnetic materials at finite temperatures. Special focus is put on the description of longitudinal magnetic fluctuations and the application in random transition metal alloys. READ MORE

  5. 3. Stochastic Resonance and Noise-Assisted Signal Transfer : On Coupling Effects of Stochastic Resonators and Spectral Optimization of Fluctuations in Random Network Switches

    Author : Peter Hammerstein; Claes Granqvist; Laszlo Kish; Hans Liljenström; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering physics; stochastic resonance; nonlinear stochastic dynamics; noise and fluctuations; magnetic domains; Teknisk fysik; Engineering physics; Teknisk fysik;

    Abstract : Recent research shows that noise or random fluctuations must not always be destructive in Nature by degrading system performance. On the contrary, in nonlinear systems they can synchronize systems or enhance the quality of signal transmission. The latter possibility is reported in the thesis. READ MORE

  6. 4. Electrified Integrated Kinetic Energy Storage

    Author : Magnus Hedlund; Hans Bernhoff; Markus Mueller; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; flywheel energy storage; magnetic bearings; carbon composite; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Abstract : The electric car is a technically efficient driveline, although it is demanding in terms of the primary energy source. Most trips are below 50 km and the mean power required for maintaining speed is quite low, but the system has to be able to both provide long range and high maximum power for acceleration. READ MORE

  7. 5. Metallic Amorphous Thin Films and Heterostructures with Tunable Magnetic Properties

    Author : Atieh Zamani; Petra Jönsson; Olof Karis; Per Nordblad; Yves Idzerda; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Amorphous; Thin Film; Magnetic properties; FeZr alloys; Ion implantation; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Abstract : The primary focus of this thesis is to study the effect of doping on magnetic properties in amorphous Fe100−xZrx alloys. Samples with compositions of x = 7,11.6 and 12 at.% were implanted with different concentrations of H. READ MORE