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arXiv · 0809.2962

Generalized gauge-invariant formulations of the strong-field approximation

Yulian V. Vanne·Alejandro Saenz
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Abstract

The gauge problem in the so-called strong-field approximation (SFA) describing atomic or molecular systems exposed to intense laser fields is investigated. Introducing a generalized gauge and partitioning of the Hamiltonian it is demonstrated that the S-matrix expansion obtained in the SFA depends on both gauge and partitioning in such a way that two gauges always yield the same S-matrix expansion, if the partitioning is properly chosen.

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Yulian V. Vanne, Alejandro Saenz. 2008-09-17. Generalized gauge-invariant formulations of the strong-field approximation. https://doi.org/10.1103/physreva.79.023421

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