Seminars Archive

Multiphoton Ionization with Shaped Femtosecond Laser

Abstract
In this talk, we give a brief introduction to frequency-domain femtosecond pulse shaping and applications for coherent control of perturbative and non-perturbative multiphoton ionization (MPI) of atoms and small molecules. An overview of some of our work can be found in [1]. We begin our discussion of coherent control with established pulse shapes such as phaselocked double- and multipulse sequences as well as chirped pulses. More advanced pulse shapes are presented including the generalized spectral step function and Airy pulses. In our recent experiments we sculpture multichromatic fields from a carrier-envelope-phase stable over-octave spanning white light supercontinuum by spectral amplitude and phase modulation. Using additional broadband polarizers and lambda plates in our pulse shaper we achieve fully polarization-tailored multichromatic fields. Applications of the shaped pulses in atomic and molecular MPI include the manipulation of dressed states [2], control of coupled electron-nuclear dynamics [3], spin-orbit [4] and Rydberg [5] wave packet dynamics along with directional photoemission [6] and the generation of free electron vortices with even [7] and odd [8] numbered rotational symmetry. [1] K. Eickhoff, L. Englert, T. Bayer and M. Wollenhaupt, Front. Phys. 9, 675258 (2021) [2] T. Bayer, M. Wollenhaupt, H. Braun and T. Baumert, Adv. Chem. Phys. 159, 235–282 (2016) [3] T. Bayer, H. Braun, C. Sarpe, R. Siemering, P. von den Hoff, R. de Vivie-Riedle, T. Baumert and M. Wollenhaupt, Physical Review Letters 110, 123003 (2013) [4] T. Bayer, D. Gräfing, S. Kerbstadt, D. Pengel, K. Eickhoff, L. Englert and M. Wollenhaupt, New J. Phys. 21, 033001 (2019) [5] K. Eickhoff, S. Kerbstadt, T. Bayer and M. Wollenhaupt, Phys. Rev. A 101, 013430 (2020) [6] S. Kerbstadt, D. Pengel, L. Englert, T. Bayer and M. Wollenhaupt, Phys. Rev. A 97, 063402 (2018) [7] D. Pengel, S. Kerbstadt, D. Johannmeyer, L. Englert, T. Bayer and M. Wollenhaupt, Phys. Rev. Lett. 118, 053003 (2017) [8] S. Kerbstadt, K. Eickhoff, T. Bayer and M. Wollenhaupt, Nature Communications 10, 658 (2019)