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On the use of the Kramers-Henneberger Hamiltonian in multi-photon ionization calculations

I. A. Ivanov·A. S. Kheifets
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Abstract

We employ the Kramers-Henneberger Hamiltonian for time-independent calculations of multi-photon ionization of atoms with one and two electrons. As compared to the electromagnetic interaction in the length and velocity gauges, the presently employed Kramers-Henneberger gauge has an advantage of the dipole matrix elements for the free-free electron transitions being finite and well-defined quantities. This circumstance simplifies considerably the computations and allows to obtain accurate results for the two-photon ionization of realistic atomic systems.

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I. A. Ivanov, A. S. Kheifets. 2005-04-19. On the use of the Kramers-Henneberger Hamiltonian in multi-photon ionization calculations. https://doi.org/10.1088/0953-4075/38/13/016

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