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arXiv · 1405.4700

Studying the universality of field induced tunnel ionization times via high-order harmonic spectroscopy

Hadas Soifer·Barry D. Bruner·Matteo Negro·Michele Devetta·Davide Faccialà·Caterina Vozzi·Sandro de Silvestri·Salvatore Stagira·Nirit Dudovich
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Abstract

High-harmonics generation spectroscopy is a promising tool for resolving electron dynamics and structure in atomic and molecular systems. This scheme, commonly described by the strong field approximation, requires a deep insight into the basic mechanism that leads to the harmonics generation. Recently, we have demonstrated the ability to resolve the first stage of the process -- field induced tunnel ionization -- by adding a weak perturbation to the strong fundamental field. Here we generalize this approach and show that the assumptions behind the strong field approximation are valid over a wide range of tunnel ionization conditions. Performing a systematic study -- modifying the fundamental wavelength, intensity and atomic system -- we observed a good agreement with quantum path analysis over a range of Keldysh parameters. The generality of this scheme opens new perspectives in high harmonics spectroscopy, holding the potential of probing large, complex molecular systems.

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Hadas Soifer, Barry D. Bruner, Matteo Negro, Michele Devetta, Davide Faccialà, Caterina Vozzi, Sandro de Silvestri, Salvatore Stagira, Nirit Dudovich. 2014-05-19. Studying the universality of field induced tunnel ionization times via high-order harmonic spectroscopy. https://doi.org/10.1088/0953-4075/47/20/204029

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