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arXiv · 0906.1938

Femtosecond laser pulse shaping for enhanced ionization

A. Castro·E. Rasanen·A. Rubio·E. K. U. Gross
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Abstract

We demonstrate how the shape of femtosecond laser pulses can be tailored in order to obtain maximal ionization of atoms or molecules. For that purpose, we have overlayed a direct-optimization scheme on top of a fully unconstrained computation of the three-dimensional time-dependent Schrodinger equation. The procedure looks for pulses that maintain the same total length and integrated intensity or fluence as a given pulse that serves as an initial guess. It allows, however, for changes in frequencies -- within a certain, predefined range -- and overall shape, leading to enhanced ionization. We illustrate the scheme by calculating ionization yields for the H2+ molecule when irradiated with short (~5 fs), high-intensity laser pulses.

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A. Castro, E. Rasanen, A. Rubio, E. K. U. Gross. 2009-06-10. Femtosecond laser pulse shaping for enhanced ionization. https://doi.org/10.1209/0295-5075/87/53001

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