title: Efficient and robust strong-field control of population transfer in sensitizer dyes with designed femtosecond laser pulses.
abstract: We demonstrate control of electronic population transfer in molecules with the help of appropriately shaped femtosecond laser pulses. To this end we investigate two photosensitizer dyes in solution being prepared in the triplet ground state. Excitation within the triplet system is followed by intersystem crossing and the corresponding singlet fluorescence is monitored as a measure of population transfer in the triplet system. We record control landscapes with respect to the fluorescence intensity on both dyes by a systematic variation of laser pulse shapes combining second order and third order dispersion. In the strong-field regime we find highly structured topologies with large areas of maximum or minimum population transfer being insensitive over a certain range of applied laser intensities thus demonstrating robustness. We then compare our experimental results with simulations on generic molecular potentials by solving the time-dependent Schrödinger equation for excitation with shaped pulses. Control landscapes with respect to population transfer confirm the general trends from experiments. An analysis of regions with maximum or minimum population transfer indicates that coherent processes are responsible for the outcome of our excitation process. The physical mechanisms of joint motion of ground and excited state wave packets or population of a vibrational eigenstate in the excited state permit us to discuss the molecular dynamics in an atom-like picture.
authors: Universität Kassel, Institut für Physik und CINSaT, Heinrich-Plett-Str. 40, 34132 Kassel, Germany.
authors: Johannes
authors: J
authors: Schneider
authors: Matthias
authors: M
authors: Wollenhaupt
authors: Andreas
authors: A
authors: Winzenburg
authors: Tim
authors: T
authors: Bayer
authors: Jens
authors: J
authors: Köhler
authors: Rüdiger
authors: R
authors: Faust
authors: Thomas
authors: T
authors: Baumert
mesh_terms: D005453:Fluorescence; D007834:Lasers; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D017319:Photosensitizing Agents / Q000138:chemical synthesis / Q000737:chemistry*; D011789:Quantum Theory; D013997:Time Factors
chemical_list: D009942:Organometallic Compounds; D017319:Photosensitizing Agents