Search for dissertations about: "surface states and resonances"

Showing result 11 - 13 of 13 swedish dissertations containing the words surface states and resonances.

  2. 11. Resonant switching and vortex dynamics in spin-flop bi-layers

    Author : Sergiy Cherepov; Vladislav Korenivski; Thomas Silva; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; spin-dynamics; MRAM; vortex; switching; Condensed matter physics; Kondenserade materiens fysik; Magnetism; Magnetism; Mesoscopic physics; Mesoskopisk fysik;

    Abstract : This thesis is a study of the static and dynamic behavior of the magne-tization in spin-flop bi-layers, which consist of two soft ferromagnetic layerscoupled by dipolar forces through a thin nonmagnetic spacer. The focus ofthe work is three fold: collective spin dynamics in the anti-parallel groundstate; resonant switching in the presence of thermal agitation; and static anddynamic behavior of the system in the vortex-pair state, with a particularemphasis on the interlayer core-core interaction. READ MORE

  4. 12. Optical characterization of Silicon-based self-assembled nanostructures

    Author : Bouchaib Adnane; Wei-Xin Ni; Per Olof Holtz; Göran Hansson; Susumo Fukatsu; Linköpings universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP;

    Abstract : This PhD thesis summarizes the work carried on the optical characterizations of some Si-based self-assembled nanostructures, particularly SiGe/Si quantum dots (QDs) and nanocrystalline (nc)-Si embedded in mesoporous silica (MS) using photoconductivity (PC), photoluminescence (PL), and photoluminescence excitation (PLE) measurements. The spectroscopic studies of SiGe/Si QDs grown on Si by molecular beam epitaxy revealed for the first time well-resolved PLE resonances. READ MORE

  5. 13. Multiple Andreev Reflection - a Microscopic Theory of ac Josephson Effect in Mesoscopic Junctions

    Author : Göran Johansson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; high-Tc superconductors; d-wave symmetry; superconducting junctions; resonant tunneling; ac Josephson effect; mesoscopic superconductivity;

    Abstract : The mechanism of multiple Andreev reflection (MAR) is a microscopic theory for electron transport in voltage biased superconducting junctions, i.e. the ac Josephson effect. In this thesis we propose a new approach for calculating the dc current from MAR. READ MORE