Sökning: "XUV"

Visar resultat 1 - 5 av 35 avhandlingar innehållade ordet XUV.

  1. 1. Spatial and temporal aspects of intense attosecond pulses for pump-probe experiments

    Författare :Hampus Wikmark; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ultrafast lasers; ultrafast optics; attosecond pulses; pump-probe experiments; XUV light; XUV focusing; wavefront sensing; XUV optics; X-ray optics; Fysicumarkivet A:2019:Wikmark; ultrasnabba lasrar; attosekundspulser; pump-prob-experiment; XUV-ljus; vågfrontmätningar; XUV-optik; Röntgen-optik;

    Sammanfattning : Nuclear and electronic dynamics in atoms and molecules are the foundation of many physical processes and chemical reactions. Often, these dynamics take place on timescales so much shorter than those commonly encountered that they are called ultrafast. LÄS MER

  3. 2. Non-linear Spectroscopy of Conical Intersections with XUV and X-ray Photons

    Författare :Deependra Jadoun; Markus Kowalewski; Faris Gelmukhanov; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Conical Intersections; Non-linear Spectroscopy; Quantum Dynamics; Perturbation Theory; Ultrafast Spectroscopy; X-ray; XUV; Theoretical Physics; teoretisk fysik;

    Sammanfattning : Conical intersections (CIs) appear in a molecule due to the breakdown of the Born-Oppenheimer approximation when the energy difference between two or more electronic states decreases. CIs are known to play a crucial role in processes such as photosynthesis and vision in the human eye, and therefore it is important to probe the existence of such entities in molecules. LÄS MER

  4. 3. Applications of Short Extreme Ultraviolet Pulses to the Spectroscopy of Atoms and Molecules

    Författare :Allan Johansson; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; High-order harmonics; short pulses; pulse characterisation; sidebands; lifetime measurements; time domain spectroscopy; frequency domain spectroscopy; He; N2; CO; XUV; Atomic and molecular physics; relative polarisation; Atom- och molekylärfysik; Fysicumarkivet A:2003:Johansson;

    Sammanfattning : This thesis is devoted to the characterisation in time and frequency, and to spectroscopic application, of extreme ultraviolet (XUV) pulses. High-order harmonic generation or wave mixing processes were used to produce the pulses in the XUV spectral region. LÄS MER

  5. 4. Constructing and Commissioning HELIOS – A High Harmonic Generation Source for Pump-Probe Measurements with sub 50 fs Temporal Resolution : The Development of Experimental Equipment for Extreme Ultraviolet Spectroscopy

    Författare :Joachim A. Terschlüsen; Johan Söderström; Margaret Murnane; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Angle-resolved photoemission spectroscopy; Angle resolved photoemission spectroscopy; Angle-resolved time-of-flight; Angle resolved time of flight; ARTOF; ARPES; tr-ARPES; fs; fs resolution; Fourier transform spectrometer; Fourier-transform spectrometer; Fourier transform spectroscopy; Fourier-transform spectroscopy; FTS; gas cell; high harmonic generation; laser; liquid jet; monochromator; HELIOS; HHG; off-plane mount; off plane mount; OPA; optical parametric amplifier; PCPDTBT; pulse shaping; pump probe; pump-probe measurements; pump-probe measurements; pump-probe spectroscopy; pump-probe spectroscopy; Rowland spectrometer; time-of-flight spectrometer; time of flight spectrometer; TOF; time-resolved spectroscopy; time resolved spectroscopy; time-resolved experiments; time resolved experiments; T-MOKE; tr-PES; PES; photoelectron spectroscopy; transverse magneto optical Kerr effect; transverse magneto-optical Kerr effect; ultrafast; ultra-high vacuum; ultra high vacuum; UHV; XUV; VUV; X-rays; Permalloy; magnetization dynamic; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : This thesis presents HELIOS, an in-house laboratory for time-resolved pump-probe spectroscopy with extreme-ultraviolet (XUV) probe radiation. A wide span of pump wavelengths can be generated using commercial laser equipment while XUV probe radiation is generated via a high harmonic generation process in a noble gas delivering probe photons with energies between 20 eV and 72 eV. LÄS MER

  7. 5. An Intense Attosecond Light Source - Towards Extreme Ultraviolet Pump-Probe Experiments

    Författare :Filippo Campi; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Attosecond; Femtosecond; Ultrashort; Ultrafast; High-order Harmonic Generation; pump probe; XUV; Fysicumarkivet A:2017:Campi;

    Sammanfattning : This thesis presents important steps towards performing high-intensity attosecond pump-probe experiments at the Lund high-intensity extreme ultraviolet (XUV) beamline, which followed two complementary paths: maximization of the XUV intensity available in the interaction region with a gas target, and providing attosecond temporal resolution.To maximize the energy of the XUV pulses generated via high-order harmonicgeneration (HHG), the macroscopic response of atoms to the driving infrared field was optimized. LÄS MER