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arXiv · 2406.08678

Harnessing Plasmonic Interference for Nanoscale Ultrafast Electron Sources

Alimohammed Kachwala·Mansoure Moeini Rizi·Christopher M Pierce·Daniele Filippetto·Jared Maxson·Siddharth Karkare
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Abstract

In this paper we demonstrate the use of plasmonic focusing in conjunction with non-linear photoemisison to develop geometrically flat nanoscale electron sources with less than 40 pm-rad root mean squared (rms) normalized transverse emittance. Circularly polarized light is incident on a gold Archimedean spiral structure to generate surface-plasmon-polaritons which interfere coherently at the center resulting in a 50 nm rms emisison area. Such a nanostructured flat surface enables simultaneous spatio-temporal confinement of emitted electrons at the nanometer and femtosecond level and can be used as an advanced electron source for high-repetition-rate ultrafast electron diffraction and microscopy experiments as well as next-generation of miniaturized particle accelerators.

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Alimohammed Kachwala, Mansoure Moeini Rizi, Christopher M Pierce, Daniele Filippetto, Jared Maxson, Siddharth Karkare. 2024-06-12. Harnessing Plasmonic Interference for Nanoscale Ultrafast Electron Sources. https://arxiv.org/abs/2406.08678

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