Publication Date:
2019
Description:
〈p〉In traditional models of heteroepitaxy, the substrate serves mainly as a crystalline template for the thin-film lattice, dictating the initial roughness of the film and the degree of coherent strain. Here, performing in situ surface x-ray diffraction during the heteroepitaxial growth of LaTiO〈sub〉3〈/sub〉 on SrTiO〈sub〉3〈/sub〉 (001), we find that a TiO〈sub〉2〈/sub〉 adlayer composed of the 〈f〉〈/f〉〈i〉R〈/i〉33.7° and 〈f〉〈/f〉〈i〉R〈/i〉45.0° reconstructions is a highly active participant in the growth process, continually diffusing to the surface throughout deposition. The effects of the TiO〈sub〉2〈/sub〉 adlayer on layer-by-layer growth are investigated using different deposition sequences and anomalous x-ray scattering, both of which permit detailed insight into the dynamic layer rearrangements that take place. Our work challenges commonly held assumptions regarding growth on TiO〈sub〉2〈/sub〉-terminated SrTiO〈sub〉3〈/sub〉 (001) and demonstrates the critical role of excess TiO〈sub〉2〈/sub〉 surface stoichiometry on the initial stages of heteroepitaxial growth on this important perovskite oxide substrate material.〈/p〉
Electronic ISSN:
2375-2548
Topics:
Natural Sciences in General
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