Ultrafast electron microscopy (UEM) has been demonstrated as an effective table-top technique for imaging the temporally evolving dynamics of matter with a subparticle spatial resolution on the timescale 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 to probe efficiently the electronic dynamics of matter. Moreover, we investigate the feasibility of attosecond optical gating to generate isolated subfemtosecond electron pulses and attain the desired temporal resolution in electron microscopy to establish ‘attomicroscopy’ to allow the imaging of electron motion in the act.
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We thank G. M. Vanacore and T. Karam for fruitful discussions. This work was supported by the National Science Foundation Grant DMR-0964886 and the Air Force Office of Scientific Research Grant FA9550-11-1-0055 for research conducted in The Gordon and Betty Moore Center for Physical Biology at the California Institute of Technology.
The authors declare no competing financial interests.
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Hassan, M., Baskin, J., Liao, B. et al. High-temporal-resolution electron microscopy for imaging ultrafast electron dynamics. Nature Photon 11, 425–430 (2017). https://doi.org/10.1038/nphoton.2017.79
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