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arXiv · 1807.00779

Strong-Field Polarizability-Enhanced Dissociative Ionization

Lun Yue·Philipp Wustelt·A. Max Sayler·Gerhard G. Paulus·Stefanie Gräfe
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Abstract

We investigate dissociative single and double ionization of HeH+ induced by intense femtosecond laser pulses. By employing a semi-classical model with nuclear trajectories moving on field-dressed surfaces and ionization events treated as stochastical jumps, we identify a strong-field mechanism wherein the molecules dynamically align along the laser polarization axis and stretch towards a critical internuclear distance before getting dissociative ionized. As the tunnel-ionization rate is greater for larger internuclear distance and for aligned samples, ionization is enhanced. The strong dynamical rotation is traced back to a maximum in the parallel component of the internuclear-distance-dependent polarizability tensor. Qualitative agreement with our experimental observations is found. Finally the criteria for observing the isotope effect for the ion angular distribution is discussed.

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Lun Yue, Philipp Wustelt, A. Max Sayler, Gerhard G. Paulus, Stefanie Gräfe. 2018-07-02. Strong-Field Polarizability-Enhanced Dissociative Ionization. https://doi.org/10.1103/physreva.98.043418

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