Sökning: "self-trapping"

Visar resultat 1 - 5 av 7 avhandlingar innehållade ordet self-trapping.

  1. 1. Influence of Self-trapping, Clamping and Confinement on Hydrogen Absorption

    Författare :Gunnar Karl Pálsson; Björgvin Hjörvarsson; Keith Ross; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; hydrogen diffusion; thin films; superlattices; phase transitions; confinement; clamping; self-trapping; finite-size effect; Surfaces and interfaces; Ytor och mellanytor; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : The dissociation of hydrogen molecules at surfaces is the first step in the absorption process. If the absorbing material is covered by an oxide, this layer will determine the effective uptake rate of an underlying absorbing material. LÄS MER

  2. 2. Nonlinear pulse propagation effects for application to optical fibre communication systems

    Författare :Anders Berntson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear fibre optics; optical solitions; pulse compression; self-phase modulation; nonlinear scrödinger equation; self-trapping; dispersion compensation; solition interaction;

    Sammanfattning : .... LÄS MER

  3. 3. Nonlinear Propagation of Optical Pulses and Beams

    Författare :Magnus Karlsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; self-phase modulation; optical wave breaking; paraxial-ray approximation; stimulated Raman scattering; nonlinear Schrödinger equation; optical collapse; modulational instability; higher-order dispersion; optical fibers; saturable nonlinearity; Kerr-nonlinearity; self-trapping; group-velocity dispersion; optical solitons; self-focusing;

    Sammanfattning : The propagation of optical beams and pulses under the influence of nonlinear effects is characterized by a rich variety of phenomena and many potentially important applications. We analyse two main topics in this context: nonlinear beam propagation, and nonlinear pulse propagation in optical fibers. LÄS MER

  4. 4. Insights into Materials Properties from Ab Initio Theory : Diffusion, Adsorption, Catalysis & Structure

    Författare :Andreas Blomqvist; Rajeev Ahuja; Christopher Wolverton; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Density functional theory; Molecular dynamics; Diffusion; Catalysis; Adsorption; Random structure search; Hydrogen-storage materials; Phase-change materials; Defects and diffusion; Defekter och diffusion; Surfaces and interfaces; Ytor och mellanytor; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : In this thesis, density functional theory (DFT) calculations and DFT based ab initio molecular dynamics simulations have been employed in order to gain insights into materials properties like diffusion, adsorption, catalysis, and structure. In transition metals, absorbed hydrogen atoms self-trap due to localization of metal d-electrons. LÄS MER

  5. 5. Collective Excitation Dynamics in Molecular Aggregates

    Författare :Mats Dahlbom; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry; Kemi; Fysik; Physics; computational methods; photosynthesis; femtosecond spectroscopy; Exciton; Polaron;

    Sammanfattning : The aim of this thesis is to study collective excitation dynamics in molecular aggregates. Half of the work presented here is method development and the remainder is application of these methods to several di.erent molecular aggregates. LÄS MER