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Strong-field ionization of atoms and molecules: The two-term saddle point method

Thomas Kim Kjeldsen·Lars Bojer Madsen
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Abstract

We derive an analytical formula for the ionization rate of neutral atoms and molecules in a strong monochromatic field. Our model is based on the strong-field approximation with transition amplitudes calculated by an extended saddle point method. We show that the present two-term saddle point method reproduces even complicated structures in angular resolved photo electron spectra.

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Thomas Kim Kjeldsen, Lars Bojer Madsen. 2006-06-02. Strong-field ionization of atoms and molecules: The two-term saddle point method. https://doi.org/10.1103/physreva.74.023407

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