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arXiv · 2410.14873

BEACON -- Automated Aberration Correction for Scanning Transmission Electron Microscopy using Bayesian Optimization

Alexander J. Pattison·Stephanie M. Ribet·Marcus M. Noack·Georgios Varnavides·Kunwoo Park·Earl Kirkland·Jungwon Park·Colin Ophus·Peter Ercius
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Abstract

Aberration correction is an important aspect of modern high-resolution scanning transmission electron microscopy. Most methods of aligning aberration correctors require specialized sample regions and are unsuitable for fine-tuning aberrations without interrupting on-going experiments. Here, we present an automated method of correcting first- and second-order aberrations called BEACON which uses Bayesian optimization of the normalized image variance to efficiently determine the optimal corrector settings. We demonstrate its use on gold nanoparticles and a hafnium dioxide thin film showing its versatility in nano- and atomic-scale experiments. BEACON can correct all first- and second-order aberrations simultaneously to achieve an initial alignment and first- and second-order aberrations independently for fine alignment. Ptychographic reconstructions are used to demonstrate an improvement in probe shape and a reduction in the target aberration.

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Alexander J. Pattison, Stephanie M. Ribet, Marcus M. Noack, Georgios Varnavides, Kunwoo Park, Earl Kirkland, Jungwon Park, Colin Ophus, Peter Ercius. 2024-10-18. BEACON -- Automated Aberration Correction for Scanning Transmission Electron Microscopy using Bayesian Optimization. https://arxiv.org/abs/2410.14873

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