Observation of dynamic Stark resonances in strong-field excitation

ORAL

Abstract

We investigated AC Stark-shifted resonances in Ar with ultrashort near-infrared light of two different durations (30 fs and 6 fs). With the 30 fs pulses, we clearly observed a periodic enhancement of the excitation yield in the intensity regions where the absorption of 13 and 14 photons occurs. When few-cycle 6 fs pulses are used, these enhancements become ambiguous due to the bandwidth of the pulse. We have a good agreement compared to simulations of the process using the TDSE and demonstrate evidence that the enhancements are due to AC Stark-shift resonances efficiently populating the 5g and 6h states.

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Authors

  • R.T. Sang

    • Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
    • Griffith University

  • D Chetty

    • Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia

  • R.D. Glover

    • Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
    • University of Adelaide

  • B.A. deHarak

    • Physics Department, Illinois Wesleyan University, Bloomington, IL 61702-2900
    • Illinois Wesleyan University

  • X.M. Tong

    • Centre for Computational Sciences, University of Tsukuba

  • H. Xu

    • Centre for Quantum Dynamics, Griffith University

  • K. Bartschat

    • Department of Physics and Astronomy, Drake University

  • Nicolas Douguet

    • Department of Physics, Kennesaw State University
    • Kennesaw University
    • Kennesaw State University
    • Dept. Physics$^3$, Kennesaw State University

  • A.N. Luiten

    • Institute for Photonics and Advanced Sensing, The University of Adelaide

  • P.S. Light

    • Institute for Photonics and Advanced Sensing, The University of Adelaide

  • I.V. Litvinyuk

    • Centre for Quantum Dynamics, Griffith University