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arXiv · 2609.30229

Molecular Beam Epitaxy of AgTaO3

Abstract

We report the first synthesis of single-crystal AgTaO3 thin films using molecular-beam epitaxy (MBE). High-quality epitaxial AgTaO3 films were grown on both (001)- and (111)-oriented SrTiO3 substrates using sequential deposition of atomic silver and TaO2 layers under an ozone/oxygen atmosphere (80 % O3 + 20 % O2). X-ray diffrac- tion and reciprocal space mapping demonstrate that the films are coherently strained to the SrTiO3 substrates with sharp rocking curves comparable to the substrates, indicating high structural perfection. High-angle annular dark-field scanning trans- mission electron microscopy (HAADF-STEM) confirms coherent, low defect growth for (001)pc-oriented films. For (111)pc-oriented films, initial coherent growth proceeds up to 10 nm before transitioning into a Ta-rich surface region. Energy-dispersive X-ray spectroscopy (EDX) reveals a narrow cation intermixing region at the sub- strate interface for both orientations. This work demonstrates an effective synthesis route for single-crystal AgTaO3 thin films, providing a platform to investigate strain engineering and emergent interfacial properties in silver-based tantalates.

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Tobias Schwaigert, Joshua Maile, Olivia Peek, Eric Biedke, Paul T. Malinowski, Kyle M. Shen, Salva Salmani-Rezaie, Darrell G. Schlom, Kaveh Ahadi. 2026-09-24. Molecular Beam Epitaxy of AgTaO3. https://arxiv.org/abs/2609.30229

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