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arXiv · 1704.04246

High-temporal-resolution electron microscopy for imaging ultrafast electron dynamics

Abstract

Ultrafast Electron Microscopy (UEM) has been demonstrated to be an effective table-top technique for imaging the temporally-evolving dynamics of matter with subparticle spatial resolution on the time scale of atomic motion. However, imaging the faster motion of electron dynamics in real time has remained beyond reach. Here, we demonstrate more than an order of magnitude (16 times) enhancement in the typical temporal resolution of UEM by generating isolated 30 fs electron pulses, accelerated at 200 keV, via the optical-gating approach, with sufficient intensity for efficiently probing the electronic dynamics of matter. Moreover, we investigate the feasibility of attosecond optical gating to generate isolated subfemtosecond electron pulses, attaining the desired temporal resolution in electron microscopy for establishing the Attomicroscopy to allow the imaging of electron motion in the act.

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M. Th. Hassan, J. S. Baskin, B. Liao, A. H. Zewail. 2017-05-29. High-temporal-resolution electron microscopy for imaging ultrafast electron dynamics. https://doi.org/10.1038/nphoton.2017.79

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