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arXiv · 2204.09997

Computational ghost imaging for transmission electron microscopy

Abstract

While transmission electron microscopes (TEM) can achieve a much higher resolution than optical microscopes, they face challenges of damage to samples during the high energy processes involved. Here, we explore using computational ghost imaging techniques in electron microscopy to reduce the total required intensity. The technological lack of the equivalent high-resolution, optical spatial light modulator for electrons means that a different approach needs to be pursued. To this end, we show a beam shaping technique based on the use of a distribution of electrically charged metal needles to structure the beam, alongside a novel reconstruction method to handle the resulting highly non-orthogonal patterns. Second, we illustrate the application of this ghost imaging approach in electron microscopy. To test the full extent of the capabilities of this technique, we realised an analogous optical setup method. In both regimes, the ability to reduce the amount of total illumination intensity is evident in comparison to raster scanning.

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BibTeXRIS

Akhil Kallepalli, Lorenzo Viani, Daan Stellinga, Enzo Rotunno, Ming-Jie Sun, Richard Bowman, Paolo Rosi, Stefano Frabboni, Roberto Balboni, Andrea Migliori, Vincenzo Grillo, Miles Padgett. 2022-04-21. Computational ghost imaging for transmission electron microscopy. https://arxiv.org/abs/2204.09997

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