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arXiv · 2205.08655

Carrier-envelope-phase and helicity control of electron vortices in photodetachment

M. M. Majczak·F. Cajiao Vélez·J. Z. Kamiński·K. Krajewska
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Abstract

Formation of electron vortices and momentum spirals in photodetachment of the H$^-$ anion driven by isolated ultrashort laser pulses of circular polarization or by pairs of such pulses (of either corotating or counterrotating polarizations) are analyzed under the scope of the strong-field approximation. It is demonstrated that the carrier-envelope phase (CEP) and helicity of each individual pulse can be used to actively manipulate and control the vortical pattern in the probability amplitude of photodetachment. Specifically, the two-dimensional mappings of probability amplitude can be rotated in the polarization plane with changing the CEP of the driving pulse (or two corotating pulses); thus, offering a new tool of field characterization. Furthermore, it is shown that the formation of spirals or annihilation of vortices relates directly to the time-reversal symmetry of the laser field, which is realized by a pair of pulses with opposite helicities and CEPs.

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M. M. Majczak, F. Cajiao Vélez, J. Z. Kamiński, K. Krajewska. 2022-05-17. Carrier-envelope-phase and helicity control of electron vortices in photodetachment. https://doi.org/10.1364/oe.473929

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