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Strong-field approximation for intense-laser atom processes: the choice of gauge

D. Bauer·D. B. Milosevic·W. Becker
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Abstract

The strong-field approximation can be and has been applied in both length gauge and velocity gauge with quantitatively conflicting answers. For ionization of negative ions with a ground state of odd parity, the predictions of the two gauges differ qualitatively: in the envelope of the angular-resolved energy spectrum, dips in one gauge correspond to humps in the other. We show that the length-gauge SFA matches the exact numerical solution of the time-dependent Schrödinger equation.

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D. Bauer, D. B. Milosevic, W. Becker. 2005-04-08. Strong-field approximation for intense-laser atom processes: the choice of gauge. https://doi.org/10.1103/physreva.72.023415

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