Atomap - Automated Analysis of Atomic Resolution STEM Images

Abstract

Atomic resolution scanning transmission electron microscopy (STEM) data contain a large amount of information about the structure of a crystalline material. Often, this information is hard to extract, due to the large number of atomic columns and large differences in intensity from sublattices consisting of different elements. Atomap is a semi-automatic, free and open source software tool for analysing both the position and shapes of atomic columns in STEM-images, using 2-D elliptical Gaussian distributions. In this work, the Atomap software is used on variants of the perovskite oxide structure, obtaining quantitative information from projected sublattices. Changes in the lattice parameters and shape of Acation columns from annular dark field images of perovskite oxide heterostructures are obtained. Furthermore, we demonstrate the functionality of Atomap by quantifying deviation from centrosymmerty of light atomic oxygen columns.