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تسجيل مستخدم جديدCoupling lattice instabilities across the interface in ultrathin oxide heterostructures
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Oxide heterointerfaces constitute a rich platform for realizing novel functionalities in condensed matter. A key aspect is the strong link between structural and electronic properties, which can be modified by interfacing materials with distinct lattice symmetries. Here we determine the effect of the cubic-tetragonal distortion of $text{SrTiO}_3$ on the electronic properties of thin films of $text{SrIrO}_3$, a topological crystalline metal hosting a delicate interplay between spin-orbit coupling and electronic correlations. We demonstrate that below the transition temperature at 105 K, $text{SrIrO}_3$ orthorhombic domains couple directly to tetragonal domains in $text{SrTiO}_3$. This forces the in-phase rotational axis to lie in-plane and creates a binary domain structure in the $text{SrIrO}_3$ film. The close proximity to the metal-insulator transition in ultrathin $text{SrIrO}_3$ causes the individual domains to have strongly anisotropic transport properties, driven by a reduction of bandwidth along the in-phase axis. The strong structure-property relationships in perovskites make these compounds particularly suitable for static and dynamic coupling at interfaces, providing a promising route towards realizing novel functionalities in oxide heterostructures.
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