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arXiv · 1602.06019

Unraveling nonadiabatic ionization and Coulomb potential effects in strong-field photoelectron holography

Abstract

Strong field photoelectron holography has been proposed as a means for interrogating the spatial and temporal information of electrons and ions in a dynamic system. After ionization, part of the electron wave packet may directly go to the detector (the reference wave), while another part may be driven back to the ion where it scatters off (the signal wave). The interference hologram of the two waves may be used to retrieve the target information. However, unlike conventional optical holography, the propagations of electron wave packets are affected by the Coulomb potential as well as by the laser field. In addition, electrons are emitted over the whole laser pulse duration, thus multiple interferences may occur. In this work, we used a generalized quantum-trajectory Monte Carlo method to investigate the effect of Coulomb potential and the nonadiabatic subcycle ionization on the photoelectron hologram. We showed that photoelectron hologram can be well described only when the nonadiabatic effect in ionization is accounted for, and Coulomb potential can be neglected only in the tunnel ionization regime. Our results help establishing photoelectron holography for probing spatial and dynamic properties of atoms and molecules.

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Xiaohong Song, Cheng Lin, Zhihao Sheng, Peng Liu, Zhangjin Chen, Weifeng Yang, Shilin Hu, C. D. Lin, Jing Chen. 2016-02-19. Unraveling nonadiabatic ionization and Coulomb potential effects in strong-field photoelectron holography. https://arxiv.org/abs/1602.06019

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