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New electron source concept for single-shot sub-100 fs electron diffraction in the 100 keV range

T. van Oudheusden·E. F. de Jong·B. J. Siwick·S. B. van der Geer·W. P. E. M. Op 't Root·O. J. Luiten
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Abstract

We present a method for producing sub-100 fs electron bunches that are suitable for single-shot ultrafast electron diffraction experiments in the 100 keV energy range. A combination of analytical results and state-of-the-art numerical simulations show that it is possible to create 100 keV, 0.1 pC, 20 fs electron bunches with a spotsize smaller than 500 micron and a transverse coherence length of 3 nm, using established technologies in a table-top set-up. The system operates in the space-charge dominated regime to produce energy-correlated bunches that are recompressed by established radio-frequency techniques. With this approach we overcome the Coulomb expansion of the bunch, providing an entirely new ultrafast electron diffraction source concept.

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T. van Oudheusden, E. F. de Jong, B. J. Siwick, S. B. van der Geer, W. P. E. M. Op 't Root, O. J. Luiten. 2007-02-02. New electron source concept for single-shot sub-100 fs electron diffraction in the 100 keV range. https://doi.org/10.1063/1.2801027

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