Sökning: "localized excitation"

Visar resultat 1 - 5 av 48 avhandlingar innehållade orden localized excitation.

  1. 1. Studies of Molecular and Cluster Fragmentation Using Synchrotron Radiation: Measurements and Models

    Författare :Andreas Lindgren; Synkrotronljusfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Atom- och molekylärfysik; Atomic and molecular physics; photoionization; synchrotron radiation; localized excitation; electron-ion coincidence; induced alignment; clusters; molecules; core excitation; mass spectroscopy; fragmentation; dissociation;

    Sammanfattning : A new spectrometer for studying photoinduced fragmentation has been designed and commissioned. The instrument produces a detailed view of the energy and angular emission of fragments, which in the case of small molecules can be related to their geometry at the moment of dissociation. LÄS MER

  3. 2. Dynamics of Excitation Transfer and Charge Separation in Polymeric Semiconductors

    Författare :Arvydas Ruseckas; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Anisotropy; Photoinduced absorption; Femtosecond spectroscopy; Polythiophene; Conjugated polymers; Donor-Acceptor Complexes; Carbazole; Charge separation; Excitation transfer; Recombination; Physics; Fysik;

    Sammanfattning : Dynamics of optically excited electronic states have been studied in solid films and solutions of semiconducting polymers and model compounds. Transient absorption, monitored in the spectral range from 0.9 eV to 2.5 eV with a time resolution of about 100 fs, was the main experimental technique. LÄS MER

  4. 3. Interaction between Electromagnetic Waves and Localized Plasma Oscillations

    Författare :Jan-Ove Hall; Thomas Leyser; Jan Trulsen; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Space and plasma physics; space physics; plasma physics; radio waves; ionospheric modification; density depleations; field-aligned irregularities; lower hybrid solitary structures; lower hybrid cavities; Z mode waves; magnetosonic waves; scattering; mode conversion; Rymd- och plasmafysik; Space physics; Rymdfysik;

    Sammanfattning : This thesis treats interaction between electromagnetic waves and localized plasma oscillations. Two specific physical systems are considered, namely artificially excited magnetic field-aligned irregularities (striations) and naturally excited lower hybrid solitary structures (LHSS). LÄS MER

  5. 4. ON THE COUPLING OF THE LOCALIZED PLASMON AND INTERBAND TRANSITIONS IN NICKEL NANOANTENNAS

    Författare :Zhaleh Pirzadeh Irannezhad; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Localized surface plasmon resonance; interband transition; nanoantenna; nickel nanoplasmonic; coupling;

    Sammanfattning : Interaction of light with metallic nanostructures smaller than the wavelength leads to excitation of collective oscillations of “free” conduction electrons. This effect leads to locally enhanced electric fields inside and outside the nanoparticle and is called localized surface plasmon resonance (LSPR). LÄS MER

  7. 5. Theoretical studies of collective electronic excitations in low-dimensional structures

    Författare :Zhe Yuan; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; linear atomic chains; hydrogen storage; nanodisks; dielectric response; surface plasmon resonances; electron gas model; electronic excitation; metallic thin films; time-dependent density functional theory;

    Sammanfattning : During the past decade, nanoplasmonics and nanophotonicshas emerged as a new branch of nanosciences with many novelapplications. Central in this development is the localized surface plasmon resonance (LSPR) tunable by the sizes and shapes at nanometer scale. LÄS MER