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HUST made breakthrough in strong-field photoelectron holography

HUST made breakthrough in strong-field photoelectron holography

On April 27th, Dr. Yueming Zhou in Huazhong University of Science and Technology and his collaborators Oleg I. Tolstikhin (Russian) and Toru Morishita (Japan) made breakthrough in research field of strong-field photoelectron holography. The result was published in Phys. Rev. Lett. 116, 173001 (2016), with the title “Near-Forward Rescattering Photoelectron Holography in Strong-Field Ionization: Extraction of the Phase of the Scattering Amplitude”.

When atoms/molecules exposed to strong laser field, tunneling ionization occurs and the ionized electron was oscillating. This oscillating electron could return to the parent ion and rescattered by the ion. This rescattering electron could be employed to image the structures of the atoms and molecules. In 2011, an experimental paper was published in Science, where the interference pattern originating from the rescattering and the tunneled electrons was observed. This type of interference was called strong-field photoelectron hologram. It is believed that this type of hologram encoded the structural information of the atoms/molecules and their ultrafast dynamics information. However, what type of structural information and how to extract this information remains unknown.

Dr. Yueming Zhou and his collaborators revisited the origination of this holographic interference. Based on the recently developed adiabatic theory they pointed out that the structural information encoded here is the phase of the scattering amplitude, which is a fundamentally important quantity in the community of atomic and molecular physics. Further, they proposed a method to decode this information, and successfully obtained this structural information from the photoelectron hologram. This establishes a novel general approach to extracting structural information from strong-field photoelectron hologram and proved the theoretical basis for time-resolved imaging of ultrafast processes in the attosecond regime with the concept of strong-field photoelectron holography.