Physical insights into the Au growth on the surface of a LaAlO₃/SrTiO₃ heterointerface

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.