Soft x-ray driven femtosecond dynamics of ionic Rydberg states in N2

ORAL

Abstract

We present the first direct observation of molecular dynamics initiated by a EUV pulse. A novel EUV pump- IR probe technique is used to observe these dynamics. The EUV pulse, with h(nu) = 42 eV, launches molecular nitrogen into highly-excited (N2)2+ core Rydberg states,~ the dynamics of which are previously unexplored. We use a time-delayed infrared pulse to promote the wavepacket from the Rydberg state to a dissociative (N2)2+ state via multiphoton ionization. The kinetic energy release of the N+/N+ channel is obtained as function of time delay. Having identified the final (N2)2+ state, we extract the potential energy curve corresponding to the evolving Rydberg state. The Rydberg state initially behaves the same as the (N2)2+ state. As the internuclear distance increases, we observe a fast decrease in the kinetic energy release on the time scale of 100 fs, corresponding to a transition from the molecular Rydberg state to N+ and N fragments.

Authors

  • Etienne Gagnon

    JILA, University of Colorado at Boulder, Boulder Co 80309

  • Arvinder Sandhu

    JILA, University of Colorado at Boulder, Boulder Co 80309, JILA, University of Colorado and NIST, Boulder, Colorado 80309-0440, USA

  • Predrag Ranitovic

    J. R. MacDonald Lab, Physics Department, Kansas State University, Manhattan Ks 66506

  • Lewis Cocke

    J. R. MacDonald Lab, Physics Department, Kansas State University, Manhattan Ks 66506, Kansas State University, J. R. Macdonald Laboratory, Kansas State University, Manhattan, Kansas 66506-2601, USA

  • Henry Kapteyn

    JILA, University of Colorado at Boulder, Boulder Co 80309, JILA, Univ. of Colorado, University of Colorado and JILA, JILA, University of Colorado and NIST, Boulder, Colorado 80309-0440, USA

  • Margaret Murnane

    JILA, University of Colorado at Boulder, Boulder Co 80309, JILA, University of Colorado and JILA, JILA, University of Colorado and NIST, Boulder, Colorado 80309-0440, USA