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arXiv · 1809.04087

Attosecond transient-absorption spectroscopy of polar molecules

Jørgen Johansen Rørstad·Nikolaj S. W. Ravn·Lun Yue·Lars Bojer Madsen
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Abstract

We apply attosecond transient absorption spectroscopy (ATAS) to explore the effects of a nonzero permanent dipole on electron dynamics at the subfemtosecond scale, exemplified in the polar LiF molecule. In contrast with nonpolar systems, a familiar feature of the ATA spectra--the light-induced structures--are observed adjacent to a bright state. Moreover, a previously unobserved ladder structure is identified. The new observations are analyzed in the context of a model based on fixed-nuclei adiabatic states, supported by full numerical simulations. Analytic calculations originating in the adiabatic model shed light on the nature and origins of the new findings.

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Jørgen Johansen Rørstad, Nikolaj S. W. Ravn, Lun Yue, Lars Bojer Madsen. 2018-09-11. Attosecond transient-absorption spectroscopy of polar molecules. https://doi.org/10.1103/physreva.98.053401

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