Characterizing multiphoton excitation using time-resolved x-ray scattering

ORAL

Abstract

Molecular iodine was photoexcited by a strong 800 nm laser, driving Raman excitation of vibrational states on the ground state as well as multiphoton dissociation. The subsequent motion following photoexcitation is observed using time-resolved x-ray scattering (TRXS) and analyzed using the temporal Fourier transform of TRXS, called frequency-resolved x-ray scattering (FRXS). The FRXS signal identifies vibrations with a beat frequency of 40.3$+$-1.0 THz oscillating about an equilibrium position of 0.28$+$-0.01nm, which match the expected beat frequency and equilibrium position for Raman excited vibrations on the ground state. Molecular dissociation also has a distinct signature in FRXS, which may be used to identify both velocities and initial positions of the dissociation channels.

*This work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Chemical Sciences, Geosciences, & Biosciences Division, Atomic, Molecular, and Optical Sciences Program.

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Authors

  • Philip Bucksbaum

    • Department of Physics, Applied Physics, and Photon Science at Stanford University, PULSE Institute
    • PULSE Institute, Stanford Universitiy/SLAC

  • Matthew Ware

    • Department of Physics at Stanford University, PULSE Institute
    • PULSE Institute, Stanford University

  • Noor Al-Sayyad

    • Department of Physics at Stanford University, PULSE Institute
    • PULSE Institute, Stanford University

  • Adi Natan

    • PULSE Institute, SLAC National Accelerator Laboratory

  • J. Michael Glownia

    • LINAC Coherent Light Source, SLAC National Laboratory
    • Linac Coherent Light Source - SLAC National Accelerator Laboratory
    • LCLS, SLAC National Accelerator Laboratory