Physics-informed Bayesian Optimization for Quantitative High-Resolution Transmission Electron Microscopy

TL;DR

This paper introduces a physics-informed Bayesian optimization framework that significantly accelerates and automates the quantitative analysis of high-resolution transmission electron microscopy images, enabling rapid, large-scale, and precise atomic structure determination.

Contribution

The work presents a novel Bayesian optimization method tailored for HRTEM quantification, improving speed and automation over traditional iterative approaches.

Findings

Achieved 3-4 orders of magnitude reduction in analysis time.

Successfully determined 3D crystal structure from a single HRTEM image.

Demonstrated applicability to complex multi-element materials.

Abstract

Quantitative high-resolution transmission electron microscopy (HRTEM) provides an indispensable means to understand the structure-property relationships of a material in atomic dimensions. Successful quantification requires reliable retrieval of essential atomic structural information despite artifacts arising from unwanted but practically unavoidable imaging imperfections. Experimental observation carried out in tandem with model-based iterative image simulation shows vast applications in quantitative structural and chemical determination of objects spanning zero to three dimensions [Prog. Mater. Sci. 133, 101037, 2023]. However, the large number of parameters involved in the simulations make the current multi-step, user-guided iterative approach highly time consuming, thereby restricting its application primarily to small sample areas and to experienced users. In this work, we implement and apply a physics-informed Bayesian optimization (BO) framework to advance HRTEM quantification towards full automation and large-field-of-view analysis. Unlike conventional optimization approaches, our method adopts a stepwise strategy that fully leverages the strength of BO in handling high-dimensional parameters, while its probabilistic engine rigorously and efficiently refines the parameter space to enable rapid quantification. Using a BaTiO3 single crystal that contains heavy, medium and light elements as a model system, we demonstrate that the three-dimensional crystal structure can be determined from a single HRTEM image with a three to four order-of-magnitude improvement in time efficiency. This approach thus opens new avenues for fast and automated image quantification over larger sample volumes and, potentially, in the time domain.