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arXiv · 2511.04897

Preparation and evaluation of alexandrite, forsterite, and topaz substrates for the epitaxial growth of rutile oxides

Monique Kubovsky·Yorick A. Birkhölzer·Luka B. Mitrovic·Hanjong Paik·George R. Rossman·Darrell G. Schlom
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Abstract

Metal-insulator transitions and superconductivity in rutile-structured oxides hold promise for advanced electronic applications, yet their thin film synthesis is severely hindered by limited substrate options. Here, we present three single- crystalline substrates, BeAl2O4, Mg2SiO4, and Al2SiO4(F,OH)2, prepared via optimized thermal and chemical treatments to achieve atomically smooth surfaces suitable for epitaxial growth. Atomic force microscopy confirms atomic step-and-terrace surface morphologies, and oxide molecular-beam epitaxy growth on these substrates demonstrates successful heteroepitaxy of rutile TiO2, VO2, NbO2, and RuO2 films. Among these unconventional substrates, BeAl2O4 exhibits exceptional thermal and chemical stability, making it a versatile substrate candidate. These findings introduce new substrate platforms that facilitate strain engineering and exploration of rutile oxide thin films, potentially advancing the study of their strain-dependent physical properties.

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Monique Kubovsky, Yorick A. Birkhölzer, Luka B. Mitrovic, Hanjong Paik, George R. Rossman, Darrell G. Schlom. 2025-11-07. Preparation and evaluation of alexandrite, forsterite, and topaz substrates for the epitaxial growth of rutile oxides. https://arxiv.org/abs/2511.04897

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