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What does materials science look like in the “Age of Artificial Intelligence?” Each material’s domain—synthesis, characterization, and modeling—has a different answer to this question, motivated by unique challenges and constraints. This work focuses on the tremendous potential of autonomous characterization within electron microscopy. We present our recent advancements in developing domain-aware, multimodal models for microscopy analysis capable of describing complex atomic systems. We then address the critical gap between the theoretical promise of autonomous microscopy and its current practical limitations, showcasing recent successes while highlighting the necessary developments to achieve robust, real-world autonomy. 

We demonstrate the epitaxial growth of the first two members, and the n=∞ member of the homologous Ruddlesden–Popper series of Ban+1InnO2.5n+1 of which the n=1 member was previously unknown. The films were grown by suboxide molecular-beam epitaxy where the indium is provided by a molecular beam of indium-suboxide [In2O (g)]. To facilitate ex situ characterization of the highly hygroscopic barium indate films, a capping layer of amorphous SiO2 was deposited prior to air exposure. The structural quality of the films was assessed by x-ray diffraction, reflective high-energy electron diffraction, and scanning transmission electron microscopy. 

Abstract The small‐polaron hopping model has been used for six decades to rationalize electronic charge transport in oxides. The model was developed for binary oxides, and, despite its significance, its accuracy has not been rigorously tested for higher‐order oxides. Here, the small‐polaron transport model is tested by using a spinel system with mixed cation oxidation states (Mn_xFe_3−xO₄). Using molecular‐beam epitaxy (MBE), a series of single crystal Mn_xFe_3−xO₄thin films with controlled stoichiometry, 0 ≤x ≤ 2.3, and lattice strain are grown, and the cation site‐occupation is determined through X‐ray emission spectroscopy (XES). Density functional theory +Uanalysis shows that charge transport occurs only between like‐cations (Fe/Fe or Mn/Mn). The site‐occupation data and percolation models show that there are limited stoichiometric ranges for transport along Fe and Mn pathways. Furthermore, due to asymmetric hopping barriers and formation energies, the polaron is energetically preferred to the polaron, resulting in an asymmetric contribution of Mn/Mn pathways. All of these findings are not contained in the conventional small‐polaron hopping model, highlighting its inadequacy. To correct the model, new parameters in the nearest‐neighbor hopping equation are introduced to account for percolation, cross‐hopping, and polaron‐distribution, and it is found that a near‐perfect correlation can be made between experiment and theory for the electronic conductivity.