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arXiv · 2002.04998

Low-Energy Interference Structure with Attosecond Temporal Resolution

Abstract

Accessing precisely to the phase variation of electronic wave-packet (EWP) provides unprecedented spatiotemporal information of microworld. A radial interference pattern at near-zero energy has been widely observed in experiments of strong-field photoionization. However, the underlying physical picture of this interference pattern is still under debate. Here we report an experimental and theoretical investigation of this low-energy interference structure (LEIS) in mid-infrared laser fields. We clarify that the LEIS arises due to the soft-recollision mechanism, which was previously found to play a pivotal role in producing the pronounced low-energy structure. Specifically, the LEIS is induced by the interference between direct and soft-recollision EWPs launched within a 1/18 laser-cycle time scale in our experiments. Moreover, the observation of LEIS is independent of laser wavelength and specific atomic targets. Our result opens a promising new avenue for retrieving the structure and dynamics of EWPs in atoms and molecules with attosecond time resolution.

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Xiaohong Song, Wenbin Jia, Xiwang Liu, Hongdan Zhang, Qibing Xue, Cheng Lin, Wei Quan, Jing Chen, XiaoJun Liu, Weifeng Yang. 2020-02-12. Low-Energy Interference Structure with Attosecond Temporal Resolution. https://doi.org/10.1088/1361-6455/ac05dd

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