Sökning: "Pump-Probe"
Visar resultat 1 - 5 av 70 avhandlingar innehållade ordet Pump-Probe.
1. 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
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
2. An Intense Attosecond Light Source - Towards Extreme Ultraviolet Pump-Probe Experiments
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
3. Infrared - X-ray pump probe spectroscopy
Sammanfattning : The present thesis concerns theoretical studies of molecular interactions investigated by infrared and X-ray spectroscopic techniques, with emphasis on using the two technologies combined in pump probe experiments. Three main types of studies are addressed: the use of near-edge X-ray absorption fine structure spectra (NEXAFS) to manifest through-bond and through-space interactions; the role of hydrogen bonding on the formation of X-ray photoelectron spectra as evidenced by simulations of the water dimer; and the development of theory, with sample applications, for infrared X-ray pump probe spectroscopy - the main theme of the thesis. LÄS MER
4. Spatial and temporal aspects of intense attosecond pulses for pump-probe experiments
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
5. Principles of Infrared - X-ray Pump-probe Spectroscopy
Sammanfattning : The present thesis concerns theoretical studies of molecular interactions investigated by infrared and X-ray spectroscopic techniques, with emphasis on using these two techniques combined in pump-probe experiments. Four main types of studies are addressed: the use of near-edge X-ray absorption fine structure spectra (NEXAFS) to manifest through-bond and through-space interactions; the role of hydrogen bonding in the formation of X-ray photoelectron spectra as evidenced by simulations of the water dimer; the development of theory, with sample applications, for infrared X-ray pump-probe spectroscopy; and molecular dynamics simulations of light-induced fragmentation of water clusters. LÄS MER