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arXiv · 1612.07137

Strong-Field Breit-Wheeler Pair Production in Two Consecutive Laser Pulses with Variable Time Delay

Martin J. A. Jansen·Carsten Müller
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Abstract

Photoproduction of electron-positron pairs by the strong-field Breit-Wheeler process in an intense laser field is studied. The laser field is assumed to consist of two consecutive short pulses, with a variable time delay in between. By numerical calculations within the framework of scalar quantum electrodynamics, we demonstrate that the time delay exerts a strong impact on the pair-creation probability. For the case when both pulses are identical, the effect is traced back to the relative quantum phase of the interfering S-matrix amplitudes and explained within a simplified analytical model. Conversely, when the two laser pulses differ from each other, the pair-creation probability depends not only on the time delay but, in general, also on the temporal order of the pulses.

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Martin J. A. Jansen, Carsten Müller. 2016-12-09. Strong-Field Breit-Wheeler Pair Production in Two Consecutive Laser Pulses with Variable Time Delay. https://doi.org/10.1016/j.physletb.2016.12.056

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