@phdthesis{Selle2007, author = {Selle, Reimer Andreas}, title = {Adaptive Polarization Pulse Shaping and Modeling of Light-Matter Interactions with Neural Networks}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-25596}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2007}, abstract = {The technique of ultrafast polarization shaping is applied to a model quantum system, the potassium dimer. The polarization dependence of the multiphoton ionization dynamics in this molecule is first investigated in pump-probe experiments, and it is then more generally addressed and exploited in an adaptive quantum control experiment utilizing near-IR polarization-shaped laser pulses. The extension of these polarization shaping techniques to the UV spectral range is presented, and methods for the generation and characterization of polarization-shaped laser pulses in the UV are introduced. Systematic scans of double-pulse sequences are introduced for the investigation and interpretation of control mechanisms. This concept is first introduced and illustrated for an optical demonstration experiment, and it is then applied for the analysis of the intrapulse dumping mechanism that is observed in the excitation of a large dye molecule in solution with ultrashort laser pulses. Shaped laser pulses are employed as a means for obtaining copious amounts of data on light-matter interactions. Neural networks are introduced as a novel tool for generating computer-based models for these interactions from the accumulated data. The viability of this approach is first tested for second harmonic generation (SHG) and molecular fluorescence processes. Neural networks are then utilized for modeling the far more complex coherent strong-field dynamics of potassium atoms.}, subject = {Lasertechnologie}, language = {en} }