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arXiv · 2308.10272

Electron Imaging of Nanoscale Charge Distributions Induced by Femtosecond Light Pulses

Jonathan T. Weber·Sascha Schäfer
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Abstract

Surface charging is a phenomenon ubiquitously observable in in-situ transmission electron microscopy of non-conducting specimens as a result of electron beam/sample interactions or optical stimuli and often limits the achievable image stability and spatial or spectral resolution. Here, we report on the electron-optical imaging of surface charging on a nanostructured surface following femtosecond-multiphoton photoemission. By quantitatively extracting the light-induced electrostatic potential and studying the charging dynamics on the relevant timescales, we gain insights into the details of the multi-photon photoemission process in the presence of a background field. We study the interaction of the charge distribution with the high-energy electron beam and secondary electrons and propose a simple model to describe the interplay of electron- and light-induced processes. In addition, we demonstrate how to mitigate sample charging by simultaneous optical illumination of the sample.

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Jonathan T. Weber, Sascha Schäfer. 2023-08-20. Electron Imaging of Nanoscale Charge Distributions Induced by Femtosecond Light Pulses. https://doi.org/10.1021/acs.nanolett.4c00773

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