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arXiv · 1506.07442

Single-Shot Electron Diffraction using a Cold Atom Electron Source

Rory W. Speirs·Corey T. Putkunz·Andrew J. McCulloch·Keith A. Nugent·Benjamin M. Sparkes·Robert E. Scholten
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Abstract

Cold atom electron sources are a promising alternative to traditional photocathode sources for use in ultrafast electron diffraction due to greatly reduced electron temperature at creation, and the potential for a corresponding increase in brightness. Here we demonstrate single-shot, nanosecond electron diffraction from monocrystalline gold using cold electron bunches generated in a cold atom electron source. The diffraction patterns have sufficient signal to allow registration of multiple single-shot images, generating an averaged image with significantly higher signal-to-noise ratio than obtained with unregistered averaging. Reflection high-energy electron diffraction (RHEED) was also demonstrated, showing that cold atom electron sources may be useful in resolving nanosecond dynamics of nanometre scale near-surface structures.

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Rory W. Speirs, Corey T. Putkunz, Andrew J. McCulloch, Keith A. Nugent, Benjamin M. Sparkes, Robert E. Scholten. 2015-06-23. Single-Shot Electron Diffraction using a Cold Atom Electron Source. https://doi.org/10.1088/0953-4075/48/21/214002

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