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arXiv · 1006.2041

Compression of sub-relativistic space-charge-dominated electron bunches for single-shot femtosecond electron diffraction

T. van Oudheusden·P. L. E. M. Pasmans·S. B. van der Geer·M. J. de Loos·M. J. van der Wiel·O. J. Luiten
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Abstract

We demonstrate compression of 95 keV, space-charge-dominated electron bunches to sub-100 fs durations. These bunches have sufficient charge (200 fC) and are of sufficient quality to capture a diffraction pattern with a single shot, which we demonstrate by a diffraction experiment on a polycrystalline gold foil. Compression is realized by means of velocity bunching as a result of a velocity chirp, induced by the oscillatory longitudinal electric field of a 3 GHz radio-frequency cavity. The arrival time jitter is measured to be 80 fs.

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T. van Oudheusden, P. L. E. M. Pasmans, S. B. van der Geer, M. J. de Loos, M. J. van der Wiel, O. J. Luiten. 2010-06-10. Compression of sub-relativistic space-charge-dominated electron bunches for single-shot femtosecond electron diffraction. https://doi.org/10.1103/physrevlett.105.264801

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