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arXiv · 2203.13425

Scattering-asymmetry control with ultrafast electron wave packet shaping

Yuya Morimoto·Peter Hommelhoff·Lars Bojer Madsen
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Abstract

Scattering of a tightly focused electron beam by an atom forms one of the bases of modern electron microscopy. A fundamental symmetry breaking occurs when the target atom is displaced from the beam center. This displacement results in a deflection of the beam and an asymmetric angular distribution of the scattered electrons. Here we propose a concept to control the sign and magnitude of the scattering asymmetry by shaping the incident high-energy electron wave packet in momentum space on the atto- to picosecond time scale. The shaping controls the ultrafast real-space dynamics of the wave packet, shifting the balance between two competing contributions of the impact-parameter-dependent quantum interference and the momentum distribution of the wave packet on the target. We find a strong sensitivity of the elastic scattering on the wave packet properties, an effect that will allow wave-packet and target characterization in ultrafast electron microscopy.

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Yuya Morimoto, Peter Hommelhoff, Lars Bojer Madsen. 2022-03-25. Scattering-asymmetry control with ultrafast electron wave packet shaping. https://doi.org/10.1088/1367-2630/ae0755

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