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Physical insights into the Au growth on the surface of a LaAlO3/SrTiO3 heterointerface† † Electronic supplementary information (ESI) available: Physical insights into Au growth on surface of LaAlO3/SrTiO3 heterointerface. See https://doi.org/10.1039/d2ra04038g

ABSTRACT: Researchers investigated the modification of the LaAlO3/SrTiO3 interface with Au overlayers and nanoparticles, which led to the change of various physical properties. However, no research is available to elucidate insights into the interaction of Au with the LaAlO3/SrTiO3 substrate. Therefore, this study is devoted to solving the question using density functional theory calculations. We also studied the optical properties of the LaAlO3/SrTiO3 system before and after the Au adsorption. We found that an additional optical peak occurs with significant intensity in the wavelength region of 600 nm to 1200 nm depending on the LaAlO3 film thickness. This peak is attributed to the increase in the hole states in the presence of Au adsorption with the increase in the LaAlO3 film thickness. Au growth on the LAO/STO substrate generates an optical peak in the wavelength region of 600–1200 nm due to the interaction of the Au s and dz2 orbitals with the O pz orbital of the LAO film.

SUBMITTER: Le O

PROVIDER: S-EPMC9403709 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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