Correlated cation lattice symmetry and oxygen octahedral rotation in perovskite oxide heterostructures

Recent studies have highlighted the collective rotations of corner-shared oxygen octahedra in ABO(3) functional perovskite oxides. However, experimental methods that allow direct measurements of oxygen octahedra, especially for the multilayer containing different types of oxygen octahedral rotations in each layer, are still rare. In this report, the correlation between oxygen octahedral rotation and cation-lattice symmetry is discussed by studying the interface-engineered perovskite La2/3Sr1/3MnO3 layers. The out-of-phase octahedral rotations remove the orthogonality between corresponding axes of the cation lattice, leading to the asymmetric diffraction pattern recorded by the reciprocal space mapping. More importantly, in the La2/3Sr1/3MnO3-multilayer heterostructure, the reciprocal space mapping can identify different octahedral rotations for each La2/3Sr1/3MnO3 layer, explaining the appearance of multiple Curie temperatures and coercive fields. Our results reveal the new understanding of the old reciprocal space mapping-based technique, based on the correlation between oxygen octahedral rotation and cation-lattice symmetry. The application of reciprocal space mapping to the La2/3Sr1/3MnO3-multilayers not only showcases the advantage of this technique but also extends our understanding of oxygen octahedral rotation to the more complicated oxide heterostructures.

Automated summary

The study analyzes the correlation between oxygen octahedral rotation and cation-lattice symmetry in ABO(3) functional perovskite oxides, using the example of interface-engineered La2/3Sr1/3MnO3 layers. It demonstrates how out-of-phase octahedral rotations can lead to asymmetric diffraction patterns in reciprocal space mapping, and how reciprocal space mapping can identify different octahedral rotations in multilayer heterostructures, providing insight into the complexities of oxide heterostructures.