Transition between mechanisms of laser-induced field-free molecular orientation.
The transition between two distinct mechanisms for the laser-induced field-free orientation of CO molecules is observed via measurements of orientation revival times and subsequent comparison to theoretical calculations. In the first mechanism, which we find responsible for the orientation of CO up to peak intensities of 8 × 10(13) W/cm(2), the molecules are impulsively oriented through the hyperpolarizability interaction. At higher intensities, asymmetric depletion through orientation-selective ionization is the dominant orienting mechanism. In addition to the clear identification of the two regimes of orientation, we propose that careful measurements of the onset of the orientation depletion mechanism as a function of the laser intensity will provide a relatively simple route to calibrating absolute rates of nonperturbative strong-field molecular ionization.
Max-Planck Institute of Quantum Optics, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany.
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Znakovskaya
Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada.
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Spanner
J. R. Macdonald Laboratory, Physics Department, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506, USA and Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064, India.
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J. R. Macdonald Laboratory, Physics Department, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506, USA.
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J. R. Macdonald Laboratory, Physics Department, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506, USA.
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Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada and Joint Attosecond Science Laboratory, University of Ottawa and National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada.
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J. R. Macdonald Laboratory, Physics Department, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506, USA and Centre for Quantum Dynamics and Australian Attosecond Science Facility, Griffith University, Nathan, Queensland 4111, Australia.
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Litvinyuk
J. R. Macdonald Laboratory, Physics Department, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506, USA.
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Max-Planck Institute of Quantum Optics, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany and J. R. Macdonald Laboratory, Physics Department, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506, USA.
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Kling