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arXiv · 2501.05157

Design for light-based spherical aberration correction of ultrafast electron microscopes

Marius Constantin Chirita Mihaila·Martin Kozák
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Abstract

We theoretically demonstrate that ponderomotive interactions near the electron cross-over can be used for aberration correction in ultrafast electron microscopes. Highly magnified electron shadow images from Si$_3$N$_4$ thin films are utilized to visualize the distortions induced by spherical aberrations. Our simulations of electron-light interactions indicate that spherical aberrations can be compensated resulting in an aberration free angle of \SI{8.1}{mrad}. For achieving the necessary light distribution, we use a gradient descent algorithm to optimize Zernike polynomials and shape the light beam into a modified Gaussian and Laguerre-Gaussian beam.

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Marius Constantin Chirita Mihaila, Martin Kozák. 2025-01-09. Design for light-based spherical aberration correction of ultrafast electron microscopes. https://doi.org/10.1364/oe.542930

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