Search for dissertations about: "magnetization"

Showing result 16 - 20 of 157 swedish dissertations containing the word magnetization.

2. 16. Spin transfer torques and spin dynamics in point contacts and spin-flop tunnel junctions

   Author : Alexander Konovalenko; Vladislav Korenivski; David W. Abraham; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; spin dynamics; spin transfer torques; point contacts; magnetization dynamics; Physics; Fysik;

   Abstract : The first part of this thesis is an experimental study of the spin-dependent transport in magnetic point contacts. Nano-contacts are produced micromechanically, by bringing a sharpened non-magnetic (N) tip into contact with a ferromagnetic (F) film. READ MORE

4. 17. Materials for Magnetic Recording Applications

   Author : Till Burkert; Olle Eriksson; Lars Nordström; Stefan Blügel; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; magnetic materials; magnetic anisotropy; saturation magnetization; magnetic data storage; superlattice; hydrogen; density functional theory; first-principles calculations; two-dimensional magnetism; FP-LMTO; EXAFS; MOKE; Fysik; Physics; Fysik;

   Abstract : In the first part of this work, the influence of hydrogen on the structural and magnetic properties of Fe/V(001) superlattices was studied. The local structure of the vanadium-hydride layers was determined by extended x-ray absorption fine structure (EXAFS) measurements. READ MORE

5. 18. Electromagnetic Modelling of Power Transformers for Study and Mitigation of Effects of GICs

   Author : Seyedali Mousavi; Göran Engdahl; Ebrahim Rahimpour; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; transformer; hysteresis; DC magnetization; GMD; GICs; FEM; reluctance network method; low frequency transients; core losses; winding losses; eddy current losses; transformator; hysteresis; DC; likströmsmagnetisering; GMD; GIC; FEM; reluktansnätverksmodell; lågfrekventa transienter; kärnförluster; lindningsförluster; virvelströmsförluster; Electrical Engineering; Elektro- och systemteknik;

   Abstract : Geomagnetic disturbances that result from solar activities can affect technological systems such as power networks. They may cause DC currents in power networks and saturation of the core in power transformers that leads to destruction in the transformer performance. READ MORE

6. 19. Ultrafast spin dynamics and relaxation in metallic ferromagnets

   Author : Vivek Unikandanunni; Stefano Bonetti; Olof Karis; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Magnetization dynamics; Three temperature model; Cobalt; Anisotropy; Electron-phonon coupling; THz; Platinum; Silver; fysik; Physics;

   Abstract : We performed ultrafast demagnetization measurements on epitaxial hcp-cobalt thin film with the easy axis in the plane of the film by pumping the sample with 400 nm radiation and probing the magneto-optic effects in the longitudinal magneto optic Kerr effect geometry using 800 nm radiation. The in-plane magnetic anisotropy of the sample enabled us to measure the demagnetization dynamics along two different crystalline directions, namely along the easy axis and at 45 degrees between the easy and hard axes. READ MORE

7. 20. Effect of Dielectric and Magnetic Material Characteristics on Frequency Response of Power Transformers

   Author : Nilanga Abeywickrama; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; frequency response analysis; dielectric insulation; Complex permeability; core magnetization; finite element method; transformer diagnosis.; high frequency modelling; magnetic viscosity; silicon steel;

   Abstract : Frequency response analysis (FRA) technique has become increasingly popular for the assessment of mechanicalintegrity in power transformers. This method is based on the fact that the shape of the frequency response at higher frequencies is uniquely determined by the geometrical construction of the transformer. READ MORE