Rare-earth oxide superlattices on Si(1Â 1Â 1)

Digital epitaxial rare-earth oxide layers are grown on Si(1 1 1) substrates by molecular beam epitaxy at substrate temperatures as low as 200 °C. It is demonstrated by X-ray diffraction and transmission electron microscopy that coherent digital layers form with an abrupt interface to the substrate. Theoretical investigations employing density functional theory demonstrate the potential in designing physical properties by strain. The large lattice mismatch of 9% between La2O3 and Lu2O3 allows for an intentional variation of the internal strain in the layers over a wide range.