Strong-Field Polarizability-Enhanced Dissociative Ionization

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.

arXiv comment7 pages

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Cited by in corpus (4)

• Tracing origins of asymmetric momentum distribution for polar molecules in strong linearly-polarized laser fields
• Characterizing Sub-Cycle Electron Dynamics of Polar Molecules by Asymmetry in Photoelectron Momentum Distributions
• Strong-field double ionization dynamics of vibrating HeH${}^{+}$ versus HeT${}^{+}$
• Local most-probable routes and classic-quantum correspondence in strong-field two-dimensional tunneling ionization