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Relativistic and retardation effects in the two--photon ionization of hydrogen--like ions

Peter Koval·Stephan Fritzsche·Andrey Surzhykov
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Abstract

The non-resonant two-photon ionization of hydrogen-like ions is studied in second-order perturbation theory, based on the Dirac equation. To carry out the summation over the complete Coulomb spectrum, a Green function approach has been applied to the computation of the ionization cross sections. Exact second-order relativistic cross sections are compared with data as obtained from a relativistic long-wavelength approximation as well as from the scaling of non-relativistic results. For high-Z ions, the relativistic wavefunction contraction may lower the two-photon ionization cross sections by a factor of two or more, while retardation effects appear less pronounced but still give rise to non-negligible contributions.

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Peter Koval, Stephan Fritzsche, Andrey Surzhykov. 2003-07-23. Relativistic and retardation effects in the two--photon ionization of hydrogen--like ions. https://doi.org/10.1088/0953-4075/36/5/307

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