[Article] - Nanoscale Characterization of Atomic Positions in Orthorhombic Perovskite Thin Films
Abstract
The crystal structure of oxide perovskites (ABO₃) governs many of their physical properties. Even minor modifications to the lattice structure can induce significant changes in functional properties, driven by the interplay among spin, orbital, and charge orders. Determining distortions and their associated symmetries is therefore a critical step in understanding the structure-property relationship. This knowledge also guides the design of epitaxial oxide heterostructures and correlated electronic states. In this study, we report an in-depth structural characterization of a 50 nm-thick LaVO₃ film grown on (110)-oriented DyScO₃ via molecular beam epitaxy. The heterostructure is investigated using a combination of X-ray diffraction, high-resolution and scanning transmission (HRTEM) electron microscopy (STEM), scanning precession electron diffraction tomography, and first-principles calculations. LaVO₃ crystallizes in the orthorhombic Pbnm space group and is constrained by the substrate, which enforces growth along the [110] orthorhombic direction across the 140 deposited unit cells. Mapping the reciprocal space enables precise determination of the film’s orientation and refinement of its lattice parameters. Using scanning transmission electron microscopy, we have analyzed the structure of LaVO₃, quantifying the antipolar displacement of the rare-earth ions. Additionally, 3D electron diffraction resolves the atomic positions of all species within the film, along with the distortions modes.
Autors
M. Martirosyan, S. Passuti, G. Masset, J. Varignon, H. Chintakindi , J. Ghanbaja, S. Migot, E. Delacotte, A. Benedit-Cárdenas, L. Pasquier, K. Dumesnil, L. Palatinus, W. Prellier, A. David, Ph. Boullay, Olivier Copie
References
Small, e02538 (2025)
DOI
