Sökning: "Laser excitation"

Visar resultat 16 - 20 av 117 avhandlingar innehållade orden Laser excitation.

  1. 16. Radiative Properties of Rare Earth Elements - Free and Bound in Crystals

    Författare :Huailiang Xu; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Laser Spectroscopy; Upconversion; Lifetimes; Atomic and molecular physics; Atom- och molekylärfysik; Laser technology; Laserteknik; Rare earth Elements; Fysicumarkivet A:2004:Xu;

    Sammanfattning : This thesis is devoted to fundamental aspects, and to spectroscopic applications of radiative properties in free atoms and ions, as well as in ions doped into crystals. Using the time-resolved laser-induced fluorescence technique, measurements of radiative lifetimes for rare earth elements have been performed in neutral Pr, Nd, Tm, and in singly ionized Sm, Er, Nd, Tm, Yb, as well as in doubly ionized Tm and Tb ions. LÄS MER

  3. 17. Ultrafast, Non-Equilibrium Electron Transfer Reactions of Molecular Complexes in Solution

    Författare :Jonas Petersson; Leif Hammarström; Antonín Vlček; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; electron transfer; laser; spectroscopy; transient absorption; anisortopy; inter ligand electron transfer; dye sensitized solar cell; DSSC; vibrational relaxation; ultrafast dynamics; fs spectroscopy; Kemi med inriktning mot kemisk fysik; Chemistry with specialization in Chemical Physics;

    Sammanfattning : Photoinduced electron transfer is a fundamentally interesting process; it occurs everywhere in the natural world. Studies on electron transfer shed light on questions about the interaction between molecules and how the dynamics of these can be utilized to steer the electron transfer processes to achieve a desired goal. LÄS MER

  4. 18. Environmental Monitoring by Multi-Spectral Lidar Techniques

    Författare :Petter Weibring; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; non-linear optics; fluorescence spectroscopy; scattering; multi-spectral imaging; Atom- och molekylärfysik; atmospheric pollution; Atomic and molecular physics; laser; remote sensing; lidar; DIAL; Fysicumarkivet A:2002:Weibring;

    Sammanfattning : Multi-spectral lidar (light detection and ranging) techniques have been developed and employed in various environmental studies, ranging from concentration mapping of volcanic emissions to fluorescence imaging of historical monuments. In both absorption measurements of gaseous species and fluorescence imaging of stones, multiple wavelength excitation and multiple wavelength detection have been applied. LÄS MER

  5. 19. Laser-driven particle acceleration - Experimental investigations

    Författare :Filip Lindau; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis describes experimental studies of laser-driven particle acceleration. With the focused intensity of today’s high-power lasers exceeding 10^18 W/cm2,extremely high-gradient accelerators are possible. LÄS MER

  7. 20. Development and Application of Laser Diagnostics for Studies of Phenomena Related to IC Engine Combustion

    Författare :Greger Juhlin; Förbränningsfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Motors and propulsion systems; framdrivningssystem; Motorer; Laser technology; Laserteknik; Fysicumarkivet A:2003:Juhlin;

    Sammanfattning : Various laser diagnostic techniques have been developed and demonstrated for engine, or engine-related measurements. The experimental work is presented in Chapter 3 and in Papers I-VII. In Chapter 3, imaging of soot in a running compression-ignition (CI) is described. LÄS MER